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* [PATCH v7 00/33] block: publish backup-top filter
@ 2021-08-04  9:37 Vladimir Sementsov-Ogievskiy
  2021-08-04  9:37 ` [PATCH v7 01/33] block: introduce bdrv_replace_child_bs() Vladimir Sementsov-Ogievskiy
                   ` (32 more replies)
  0 siblings, 33 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:37 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

Hi all!

v7: small change: keep fleecing detection logic. I'm now implementing a
more effective way to do fleecing, that doesn't rely on backing chain
and on serializing requests. So, for this alternative way we'll not need
BDRV_REQ_SERIALISING flag. Let's keep automatic addition of this flag
when backing-based fleecing detected.
So, 06 is changed and renamed, 07 rebased on it.

Patches without r-b: 6, 7, 8, 17, 18

Vladimir Sementsov-Ogievskiy (33):
  block: introduce bdrv_replace_child_bs()
  block: introduce blk_replace_bs
  qdev-properties: PropertyInfo: add realized_set_allowed field
  qdev: allow setting drive property for realized device
  block: rename backup-top to copy-before-write
  block-copy: move detecting fleecing scheme to block-copy
  block/block-copy: introduce block_copy_set_copy_opts()
  block/backup: set copy_range and compress after filter insertion
  block/backup: move cluster size calculation to block-copy
  block/copy-before-write: relax permission requirements when no parents
  block/copy-before-write: drop extra bdrv_unref on failure path
  block/copy-before-write: use file child instead of backing
  block/copy-before-write: bdrv_cbw_append(): replace child at last
  block/copy-before-write: introduce cbw_init()
  block/copy-before-write: cbw_init(): rename variables
  block/copy-before-write: cbw_init(): use file child after attaching
  block/copy-before-write: bdrv_cbw_append(): drop unused compress arg
  block/copy-before-write: cbw_init(): use options
  block/copy-before-write: initialize block-copy bitmap
  block/block-copy: make setting progress optional
  block/copy-before-write: make public block driver
  qapi: publish copy-before-write filter
  python/qemu/machine.py: refactor _qemu_args()
  python/qemu/machine: QEMUMachine: improve qmp() method
  iotests.py: VM: add own __enter__ method
  iotests/222: fix pylint and mypy complains
  iotests/222: constantly use single quotes for strings
  iotests: move 222 to tests/image-fleecing
  iotests.py: hmp_qemu_io: support qdev
  iotests/image-fleecing: proper source device
  iotests/image-fleecing: rename tgt_node
  iotests/image-fleecing: prepare for adding new test-case
  iotests/image-fleecing: add test-case for copy-before-write filter

 qapi/block-core.json                        |  25 +-
 block/{backup-top.h => copy-before-write.h} |  25 +-
 include/block/block-copy.h                  |   6 +-
 include/block/block.h                       |   2 +
 include/hw/qdev-properties.h                |   1 +
 include/sysemu/block-backend.h              |   1 +
 block.c                                     |  31 +++
 block/backup-top.c                          | 253 -------------------
 block/backup.c                              | 116 ++-------
 block/block-backend.c                       |   8 +
 block/block-copy.c                          | 135 ++++++++---
 block/copy-before-write.c                   | 256 ++++++++++++++++++++
 hw/core/qdev-properties-system.c            |  43 +++-
 hw/core/qdev-properties.c                   |   6 +-
 MAINTAINERS                                 |   4 +-
 block/meson.build                           |   2 +-
 python/qemu/machine/machine.py              |  30 ++-
 tests/qemu-iotests/222                      | 159 ------------
 tests/qemu-iotests/222.out                  |  67 -----
 tests/qemu-iotests/283                      |  35 ++-
 tests/qemu-iotests/283.out                  |   4 +-
 tests/qemu-iotests/297                      |   2 +-
 tests/qemu-iotests/iotests.py               |   9 +-
 tests/qemu-iotests/tests/image-fleecing     | 192 +++++++++++++++
 tests/qemu-iotests/tests/image-fleecing.out | 139 +++++++++++
 25 files changed, 882 insertions(+), 669 deletions(-)
 rename block/{backup-top.h => copy-before-write.h} (56%)
 delete mode 100644 block/backup-top.c
 create mode 100644 block/copy-before-write.c
 delete mode 100755 tests/qemu-iotests/222
 delete mode 100644 tests/qemu-iotests/222.out
 create mode 100755 tests/qemu-iotests/tests/image-fleecing
 create mode 100644 tests/qemu-iotests/tests/image-fleecing.out

-- 
2.29.2



^ permalink raw reply	[flat|nested] 47+ messages in thread

* [PATCH v7 01/33] block: introduce bdrv_replace_child_bs()
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:37 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:37 ` [PATCH v7 02/33] block: introduce blk_replace_bs Vladimir Sementsov-Ogievskiy
                   ` (31 subsequent siblings)
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:37 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

Add function to transactionally replace bs inside BdrvChild.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 include/block/block.h |  2 ++
 block.c               | 31 +++++++++++++++++++++++++++++++
 2 files changed, 33 insertions(+)

diff --git a/include/block/block.h b/include/block/block.h
index 3477290f9a..740038a892 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -361,6 +361,8 @@ int bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top,
                 Error **errp);
 int bdrv_replace_node(BlockDriverState *from, BlockDriverState *to,
                       Error **errp);
+int bdrv_replace_child_bs(BdrvChild *child, BlockDriverState *new_bs,
+                          Error **errp);
 BlockDriverState *bdrv_insert_node(BlockDriverState *bs, QDict *node_options,
                                    int flags, Error **errp);
 int bdrv_drop_filter(BlockDriverState *bs, Error **errp);
diff --git a/block.c b/block.c
index e97ce0b1c8..b2b66263f9 100644
--- a/block.c
+++ b/block.c
@@ -5048,6 +5048,37 @@ out:
     return ret;
 }
 
+/* Not for empty child */
+int bdrv_replace_child_bs(BdrvChild *child, BlockDriverState *new_bs,
+                          Error **errp)
+{
+    int ret;
+    Transaction *tran = tran_new();
+    g_autoptr(GHashTable) found = NULL;
+    g_autoptr(GSList) refresh_list = NULL;
+    BlockDriverState *old_bs = child->bs;
+
+    bdrv_ref(old_bs);
+    bdrv_drained_begin(old_bs);
+    bdrv_drained_begin(new_bs);
+
+    bdrv_replace_child_tran(child, new_bs, tran);
+
+    found = g_hash_table_new(NULL, NULL);
+    refresh_list = bdrv_topological_dfs(refresh_list, found, old_bs);
+    refresh_list = bdrv_topological_dfs(refresh_list, found, new_bs);
+
+    ret = bdrv_list_refresh_perms(refresh_list, NULL, tran, errp);
+
+    tran_finalize(tran, ret);
+
+    bdrv_drained_end(old_bs);
+    bdrv_drained_end(new_bs);
+    bdrv_unref(old_bs);
+
+    return ret;
+}
+
 static void bdrv_delete(BlockDriverState *bs)
 {
     assert(bdrv_op_blocker_is_empty(bs));
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 02/33] block: introduce blk_replace_bs
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
  2021-08-04  9:37 ` [PATCH v7 01/33] block: introduce bdrv_replace_child_bs() Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:37 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:37 ` [PATCH v7 03/33] qdev-properties: PropertyInfo: add realized_set_allowed field Vladimir Sementsov-Ogievskiy
                   ` (30 subsequent siblings)
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:37 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

Add function to change bs inside blk.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 include/sysemu/block-backend.h | 1 +
 block/block-backend.c          | 8 ++++++++
 2 files changed, 9 insertions(+)

diff --git a/include/sysemu/block-backend.h b/include/sysemu/block-backend.h
index 9ac5f7bbd3..29d4fdbf63 100644
--- a/include/sysemu/block-backend.h
+++ b/include/sysemu/block-backend.h
@@ -102,6 +102,7 @@ BlockBackend *blk_by_public(BlockBackendPublic *public);
 BlockDriverState *blk_bs(BlockBackend *blk);
 void blk_remove_bs(BlockBackend *blk);
 int blk_insert_bs(BlockBackend *blk, BlockDriverState *bs, Error **errp);
+int blk_replace_bs(BlockBackend *blk, BlockDriverState *new_bs, Error **errp);
 bool bdrv_has_blk(BlockDriverState *bs);
 bool bdrv_is_root_node(BlockDriverState *bs);
 int blk_set_perm(BlockBackend *blk, uint64_t perm, uint64_t shared_perm,
diff --git a/block/block-backend.c b/block/block-backend.c
index deb55c272e..6140d133e2 100644
--- a/block/block-backend.c
+++ b/block/block-backend.c
@@ -869,6 +869,14 @@ int blk_insert_bs(BlockBackend *blk, BlockDriverState *bs, Error **errp)
     return 0;
 }
 
+/*
+ * Change BlockDriverState associated with @blk.
+ */
+int blk_replace_bs(BlockBackend *blk, BlockDriverState *new_bs, Error **errp)
+{
+    return bdrv_replace_child_bs(blk->root, new_bs, errp);
+}
+
 /*
  * Sets the permission bitmasks that the user of the BlockBackend needs.
  */
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 03/33] qdev-properties: PropertyInfo: add realized_set_allowed field
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
  2021-08-04  9:37 ` [PATCH v7 01/33] block: introduce bdrv_replace_child_bs() Vladimir Sementsov-Ogievskiy
  2021-08-04  9:37 ` [PATCH v7 02/33] block: introduce blk_replace_bs Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:37 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:37 ` [PATCH v7 04/33] qdev: allow setting drive property for realized device Vladimir Sementsov-Ogievskiy
                   ` (29 subsequent siblings)
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:37 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

Add field, so property can declare support for setting the property
when device is realized. To be used in the following commit.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 include/hw/qdev-properties.h | 1 +
 hw/core/qdev-properties.c    | 6 +++---
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/include/hw/qdev-properties.h b/include/hw/qdev-properties.h
index 0ef97d60ce..f7925f67d0 100644
--- a/include/hw/qdev-properties.h
+++ b/include/hw/qdev-properties.h
@@ -32,6 +32,7 @@ struct PropertyInfo {
     const char *name;
     const char *description;
     const QEnumLookup *enum_table;
+    bool realized_set_allowed; /* allow setting property on realized device */
     int (*print)(Object *obj, Property *prop, char *dest, size_t len);
     void (*set_default_value)(ObjectProperty *op, const Property *prop);
     ObjectProperty *(*create)(ObjectClass *oc, const char *name,
diff --git a/hw/core/qdev-properties.c b/hw/core/qdev-properties.c
index 50f40949f5..c34aac6ebc 100644
--- a/hw/core/qdev-properties.c
+++ b/hw/core/qdev-properties.c
@@ -26,11 +26,11 @@ void qdev_prop_set_after_realize(DeviceState *dev, const char *name,
 
 /* returns: true if property is allowed to be set, false otherwise */
 static bool qdev_prop_allow_set(Object *obj, const char *name,
-                                Error **errp)
+                                const PropertyInfo *info, Error **errp)
 {
     DeviceState *dev = DEVICE(obj);
 
-    if (dev->realized) {
+    if (dev->realized && !info->realized_set_allowed) {
         qdev_prop_set_after_realize(dev, name, errp);
         return false;
     }
@@ -79,7 +79,7 @@ static void field_prop_set(Object *obj, Visitor *v, const char *name,
 {
     Property *prop = opaque;
 
-    if (!qdev_prop_allow_set(obj, name, errp)) {
+    if (!qdev_prop_allow_set(obj, name, prop->info, errp)) {
         return;
     }
 
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 04/33] qdev: allow setting drive property for realized device
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (2 preceding siblings ...)
  2021-08-04  9:37 ` [PATCH v7 03/33] qdev-properties: PropertyInfo: add realized_set_allowed field Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:37 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:37 ` [PATCH v7 05/33] block: rename backup-top to copy-before-write Vladimir Sementsov-Ogievskiy
                   ` (28 subsequent siblings)
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:37 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

We need an ability to insert filters above top block node, attached to
block device. It can't be achieved with blockdev-reopen command. So, we
want do it with help of qom-set.

Intended usage:

Assume there is a node A that is attached to some guest device.

1. blockdev-add to create a filter node B that has A as its child.

2. qom-set to change the node attached to the guest device’s
   BlockBackend from A to B.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 hw/core/qdev-properties-system.c | 43 +++++++++++++++++++++++---------
 1 file changed, 31 insertions(+), 12 deletions(-)

diff --git a/hw/core/qdev-properties-system.c b/hw/core/qdev-properties-system.c
index 2760c21f11..e71f5d64d1 100644
--- a/hw/core/qdev-properties-system.c
+++ b/hw/core/qdev-properties-system.c
@@ -36,11 +36,11 @@
 
 static bool check_prop_still_unset(Object *obj, const char *name,
                                    const void *old_val, const char *new_val,
-                                   Error **errp)
+                                   bool allow_override, Error **errp)
 {
     const GlobalProperty *prop = qdev_find_global_prop(obj, name);
 
-    if (!old_val) {
+    if (!old_val || (!prop && allow_override)) {
         return true;
     }
 
@@ -93,16 +93,34 @@ static void set_drive_helper(Object *obj, Visitor *v, const char *name,
     BlockBackend *blk;
     bool blk_created = false;
     int ret;
+    BlockDriverState *bs;
+    AioContext *ctx;
 
     if (!visit_type_str(v, name, &str, errp)) {
         return;
     }
 
-    /*
-     * TODO Should this really be an error?  If no, the old value
-     * needs to be released before we store the new one.
-     */
-    if (!check_prop_still_unset(obj, name, *ptr, str, errp)) {
+    if (!check_prop_still_unset(obj, name, *ptr, str, true, errp)) {
+        return;
+    }
+
+    if (*ptr) {
+        /* BlockBackend alread exists. So, we want to change attached node */
+        blk = *ptr;
+        ctx = blk_get_aio_context(blk);
+        bs = bdrv_lookup_bs(NULL, str, errp);
+        if (!bs) {
+            return;
+        }
+
+        if (ctx != bdrv_get_aio_context(bs)) {
+            error_setg(errp, "Different aio context is not supported for new "
+                       "node");
+        }
+
+        aio_context_acquire(ctx);
+        blk_replace_bs(blk, bs, errp);
+        aio_context_release(ctx);
         return;
     }
 
@@ -114,7 +132,7 @@ static void set_drive_helper(Object *obj, Visitor *v, const char *name,
 
     blk = blk_by_name(str);
     if (!blk) {
-        BlockDriverState *bs = bdrv_lookup_bs(NULL, str, NULL);
+        bs = bdrv_lookup_bs(NULL, str, NULL);
         if (bs) {
             /*
              * If the device supports iothreads, it will make sure to move the
@@ -123,8 +141,7 @@ static void set_drive_helper(Object *obj, Visitor *v, const char *name,
              * aware of iothreads require their BlockBackends to be in the main
              * AioContext.
              */
-            AioContext *ctx = iothread ? bdrv_get_aio_context(bs) :
-                                         qemu_get_aio_context();
+            ctx = iothread ? bdrv_get_aio_context(bs) : qemu_get_aio_context();
             blk = blk_new(ctx, 0, BLK_PERM_ALL);
             blk_created = true;
 
@@ -196,6 +213,7 @@ static void release_drive(Object *obj, const char *name, void *opaque)
 const PropertyInfo qdev_prop_drive = {
     .name  = "str",
     .description = "Node name or ID of a block device to use as a backend",
+    .realized_set_allowed = true,
     .get   = get_drive,
     .set   = set_drive,
     .release = release_drive,
@@ -204,6 +222,7 @@ const PropertyInfo qdev_prop_drive = {
 const PropertyInfo qdev_prop_drive_iothread = {
     .name  = "str",
     .description = "Node name or ID of a block device to use as a backend",
+    .realized_set_allowed = true,
     .get   = get_drive,
     .set   = set_drive_iothread,
     .release = release_drive,
@@ -238,7 +257,7 @@ static void set_chr(Object *obj, Visitor *v, const char *name, void *opaque,
      * TODO Should this really be an error?  If no, the old value
      * needs to be released before we store the new one.
      */
-    if (!check_prop_still_unset(obj, name, be->chr, str, errp)) {
+    if (!check_prop_still_unset(obj, name, be->chr, str, false, errp)) {
         return;
     }
 
@@ -408,7 +427,7 @@ static void set_netdev(Object *obj, Visitor *v, const char *name,
          * TODO Should this really be an error?  If no, the old value
          * needs to be released before we store the new one.
          */
-        if (!check_prop_still_unset(obj, name, ncs[i], str, errp)) {
+        if (!check_prop_still_unset(obj, name, ncs[i], str, false, errp)) {
             goto out;
         }
 
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 05/33] block: rename backup-top to copy-before-write
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (3 preceding siblings ...)
  2021-08-04  9:37 ` [PATCH v7 04/33] qdev: allow setting drive property for realized device Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:37 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:37 ` [PATCH v7 06/33] block-copy: move detecting fleecing scheme to block-copy Vladimir Sementsov-Ogievskiy
                   ` (27 subsequent siblings)
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:37 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

We are going to convert backup_top to full featured public filter,
which can be used in separate of backup job. Start from renaming from
"how it used" to "what it does".

While updating comments in 283 iotest, drop and rephrase also things
about ".active", as this field is now dropped, and filter doesn't have
"inactive" mode.

Note that this change may be considered as incompatible interface
change, as backup-top filter format name was visible through
query-block and query-named-block-nodes.

Still, consider the following reasoning:

1. backup-top was never documented, so if someone depends on format
   name (for driver that can't be used other than it is automatically
   inserted on backup job start), it's a kind of "undocumented feature
   use". So I think we are free to change it.

2. There is a hope, that there is no such users: it's a lot more native
   to give a good node-name to backup-top filter if need to operate
   with it somehow, and don't touch format name.

3. Another "incompatible" change in further commit would be moving
   copy-before-write filter from using backing child to file child. And
   this is even more reasonable than renaming: for now all public
   filters are file-child based.

So, it's a risky change, but risk seems small and good interface worth
it.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 block/{backup-top.h => copy-before-write.h} |  28 +++---
 block/backup.c                              |  22 ++---
 block/{backup-top.c => copy-before-write.c} | 100 ++++++++++----------
 MAINTAINERS                                 |   4 +-
 block/meson.build                           |   2 +-
 tests/qemu-iotests/283                      |  35 +++----
 tests/qemu-iotests/283.out                  |   4 +-
 7 files changed, 95 insertions(+), 100 deletions(-)
 rename block/{backup-top.h => copy-before-write.h} (56%)
 rename block/{backup-top.c => copy-before-write.c} (62%)

diff --git a/block/backup-top.h b/block/copy-before-write.h
similarity index 56%
rename from block/backup-top.h
rename to block/copy-before-write.h
index b28b0031c4..5977b7aa31 100644
--- a/block/backup-top.h
+++ b/block/copy-before-write.h
@@ -1,10 +1,10 @@
 /*
- * backup-top filter driver
+ * copy-before-write 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.
+ * Copyright (c) 2018-2021 Virtuozzo International GmbH.
  *
  * Author:
  *  Sementsov-Ogievskiy Vladimir <vsementsov@virtuozzo.com>
@@ -23,20 +23,20 @@
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 
-#ifndef BACKUP_TOP_H
-#define BACKUP_TOP_H
+#ifndef COPY_BEFORE_WRITE_H
+#define COPY_BEFORE_WRITE_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,
-                                         BackupPerf *perf,
-                                         BdrvRequestFlags write_flags,
-                                         BlockCopyState **bcs,
-                                         Error **errp);
-void bdrv_backup_top_drop(BlockDriverState *bs);
+BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
+                                  BlockDriverState *target,
+                                  const char *filter_node_name,
+                                  uint64_t cluster_size,
+                                  BackupPerf *perf,
+                                  BdrvRequestFlags write_flags,
+                                  BlockCopyState **bcs,
+                                  Error **errp);
+void bdrv_cbw_drop(BlockDriverState *bs);
 
-#endif /* BACKUP_TOP_H */
+#endif /* COPY_BEFORE_WRITE_H */
diff --git a/block/backup.c b/block/backup.c
index bd3614ce70..ac91821b08 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -27,13 +27,13 @@
 #include "qemu/bitmap.h"
 #include "qemu/error-report.h"
 
-#include "block/backup-top.h"
+#include "block/copy-before-write.h"
 
 #define BACKUP_CLUSTER_SIZE_DEFAULT (1 << 16)
 
 typedef struct BackupBlockJob {
     BlockJob common;
-    BlockDriverState *backup_top;
+    BlockDriverState *cbw;
     BlockDriverState *source_bs;
     BlockDriverState *target_bs;
 
@@ -104,7 +104,7 @@ static void backup_clean(Job *job)
 {
     BackupBlockJob *s = container_of(job, BackupBlockJob, common.job);
     block_job_remove_all_bdrv(&s->common);
-    bdrv_backup_top_drop(s->backup_top);
+    bdrv_cbw_drop(s->cbw);
 }
 
 void backup_do_checkpoint(BlockJob *job, Error **errp)
@@ -408,7 +408,7 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
     BackupBlockJob *job = NULL;
     int64_t cluster_size;
     BdrvRequestFlags write_flags;
-    BlockDriverState *backup_top = NULL;
+    BlockDriverState *cbw = NULL;
     BlockCopyState *bcs = NULL;
 
     assert(bs);
@@ -521,22 +521,22 @@ 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,
+    cbw = bdrv_cbw_append(bs, target, filter_node_name,
                                         cluster_size, perf,
                                         write_flags, &bcs, errp);
-    if (!backup_top) {
+    if (!cbw) {
         goto error;
     }
 
     /* job->len is fixed, so we can't allow resize */
-    job = block_job_create(job_id, &backup_job_driver, txn, backup_top,
+    job = block_job_create(job_id, &backup_job_driver, txn, cbw,
                            0, BLK_PERM_ALL,
                            speed, creation_flags, cb, opaque, errp);
     if (!job) {
         goto error;
     }
 
-    job->backup_top = backup_top;
+    job->cbw = cbw;
     job->source_bs = bs;
     job->target_bs = target;
     job->on_source_error = on_source_error;
@@ -552,7 +552,7 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
     block_copy_set_progress_meter(bcs, &job->common.job.progress);
     block_copy_set_speed(bcs, speed);
 
-    /* Required permissions are already taken by backup-top target */
+    /* Required permissions are taken by copy-before-write filter target */
     block_job_add_bdrv(&job->common, "target", target, 0, BLK_PERM_ALL,
                        &error_abort);
 
@@ -562,8 +562,8 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
     if (sync_bitmap) {
         bdrv_reclaim_dirty_bitmap(sync_bitmap, NULL);
     }
-    if (backup_top) {
-        bdrv_backup_top_drop(backup_top);
+    if (cbw) {
+        bdrv_cbw_drop(cbw);
     }
 
     return NULL;
diff --git a/block/backup-top.c b/block/copy-before-write.c
similarity index 62%
rename from block/backup-top.c
rename to block/copy-before-write.c
index 425e3778be..0dc5a107cf 100644
--- a/block/backup-top.c
+++ b/block/copy-before-write.c
@@ -1,10 +1,10 @@
 /*
- * backup-top filter driver
+ * copy-before-write 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.
+ * Copyright (c) 2018-2021 Virtuozzo International GmbH.
  *
  * Author:
  *  Sementsov-Ogievskiy Vladimir <vsementsov@virtuozzo.com>
@@ -32,25 +32,25 @@
 #include "block/qdict.h"
 #include "block/block-copy.h"
 
-#include "block/backup-top.h"
+#include "block/copy-before-write.h"
 
-typedef struct BDRVBackupTopState {
+typedef struct BDRVCopyBeforeWriteState {
     BlockCopyState *bcs;
     BdrvChild *target;
     int64_t cluster_size;
-} BDRVBackupTopState;
+} BDRVCopyBeforeWriteState;
 
-static coroutine_fn int backup_top_co_preadv(
+static coroutine_fn int cbw_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, BdrvRequestFlags flags)
+static coroutine_fn int cbw_do_copy_before_write(BlockDriverState *bs,
+        uint64_t offset, uint64_t bytes, BdrvRequestFlags flags)
 {
-    BDRVBackupTopState *s = bs->opaque;
+    BDRVCopyBeforeWriteState *s = bs->opaque;
     uint64_t off, end;
 
     if (flags & BDRV_REQ_WRITE_UNCHANGED) {
@@ -63,10 +63,10 @@ static coroutine_fn int backup_top_cbw(BlockDriverState *bs, uint64_t offset,
     return block_copy(s->bcs, off, end - off, true);
 }
 
-static int coroutine_fn backup_top_co_pdiscard(BlockDriverState *bs,
-                                               int64_t offset, int bytes)
+static int coroutine_fn cbw_co_pdiscard(BlockDriverState *bs,
+                                        int64_t offset, int bytes)
 {
-    int ret = backup_top_cbw(bs, offset, bytes, 0);
+    int ret = cbw_do_copy_before_write(bs, offset, bytes, 0);
     if (ret < 0) {
         return ret;
     }
@@ -74,10 +74,10 @@ static int coroutine_fn backup_top_co_pdiscard(BlockDriverState *bs,
     return bdrv_co_pdiscard(bs->backing, offset, bytes);
 }
 
-static int coroutine_fn backup_top_co_pwrite_zeroes(BlockDriverState *bs,
+static int coroutine_fn cbw_co_pwrite_zeroes(BlockDriverState *bs,
         int64_t offset, int bytes, BdrvRequestFlags flags)
 {
-    int ret = backup_top_cbw(bs, offset, bytes, flags);
+    int ret = cbw_do_copy_before_write(bs, offset, bytes, flags);
     if (ret < 0) {
         return ret;
     }
@@ -85,12 +85,12 @@ static int coroutine_fn backup_top_co_pwrite_zeroes(BlockDriverState *bs,
     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)
+static coroutine_fn int cbw_co_pwritev(BlockDriverState *bs,
+                                       uint64_t offset,
+                                       uint64_t bytes,
+                                       QEMUIOVector *qiov, int flags)
 {
-    int ret = backup_top_cbw(bs, offset, bytes, flags);
+    int ret = cbw_do_copy_before_write(bs, offset, bytes, flags);
     if (ret < 0) {
         return ret;
     }
@@ -98,7 +98,7 @@ static coroutine_fn int backup_top_co_pwritev(BlockDriverState *bs,
     return bdrv_co_pwritev(bs->backing, offset, bytes, qiov, flags);
 }
 
-static int coroutine_fn backup_top_co_flush(BlockDriverState *bs)
+static int coroutine_fn cbw_co_flush(BlockDriverState *bs)
 {
     if (!bs->backing) {
         return 0;
@@ -107,7 +107,7 @@ static int coroutine_fn backup_top_co_flush(BlockDriverState *bs)
     return bdrv_co_flush(bs->backing->bs);
 }
 
-static void backup_top_refresh_filename(BlockDriverState *bs)
+static void cbw_refresh_filename(BlockDriverState *bs)
 {
     if (bs->backing == NULL) {
         /*
@@ -120,11 +120,11 @@ static void backup_top_refresh_filename(BlockDriverState *bs)
             bs->backing->bs->filename);
 }
 
-static void backup_top_child_perm(BlockDriverState *bs, BdrvChild *c,
-                                  BdrvChildRole role,
-                                  BlockReopenQueue *reopen_queue,
-                                  uint64_t perm, uint64_t shared,
-                                  uint64_t *nperm, uint64_t *nshared)
+static void cbw_child_perm(BlockDriverState *bs, BdrvChild *c,
+                           BdrvChildRole role,
+                           BlockReopenQueue *reopen_queue,
+                           uint64_t perm, uint64_t shared,
+                           uint64_t *nperm, uint64_t *nshared)
 {
     if (!(role & BDRV_CHILD_FILTERED)) {
         /*
@@ -149,41 +149,41 @@ static void backup_top_child_perm(BlockDriverState *bs, BdrvChild *c,
     }
 }
 
-BlockDriver bdrv_backup_top_filter = {
-    .format_name = "backup-top",
-    .instance_size = sizeof(BDRVBackupTopState),
+BlockDriver bdrv_cbw_filter = {
+    .format_name = "copy-before-write",
+    .instance_size = sizeof(BDRVCopyBeforeWriteState),
 
-    .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_preadv             = cbw_co_preadv,
+    .bdrv_co_pwritev            = cbw_co_pwritev,
+    .bdrv_co_pwrite_zeroes      = cbw_co_pwrite_zeroes,
+    .bdrv_co_pdiscard           = cbw_co_pdiscard,
+    .bdrv_co_flush              = cbw_co_flush,
 
-    .bdrv_refresh_filename      = backup_top_refresh_filename,
+    .bdrv_refresh_filename      = cbw_refresh_filename,
 
-    .bdrv_child_perm            = backup_top_child_perm,
+    .bdrv_child_perm            = cbw_child_perm,
 
     .is_filter = true,
 };
 
-BlockDriverState *bdrv_backup_top_append(BlockDriverState *source,
-                                         BlockDriverState *target,
-                                         const char *filter_node_name,
-                                         uint64_t cluster_size,
-                                         BackupPerf *perf,
-                                         BdrvRequestFlags write_flags,
-                                         BlockCopyState **bcs,
-                                         Error **errp)
+BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
+                                  BlockDriverState *target,
+                                  const char *filter_node_name,
+                                  uint64_t cluster_size,
+                                  BackupPerf *perf,
+                                  BdrvRequestFlags write_flags,
+                                  BlockCopyState **bcs,
+                                  Error **errp)
 {
     ERRP_GUARD();
     int ret;
-    BDRVBackupTopState *state;
+    BDRVCopyBeforeWriteState *state;
     BlockDriverState *top;
     bool appended = false;
 
     assert(source->total_sectors == target->total_sectors);
 
-    top = bdrv_new_open_driver(&bdrv_backup_top_filter, filter_node_name,
+    top = bdrv_new_open_driver(&bdrv_cbw_filter, filter_node_name,
                                BDRV_O_RDWR, errp);
     if (!top) {
         return NULL;
@@ -210,7 +210,7 @@ BlockDriverState *bdrv_backup_top_append(BlockDriverState *source,
 
     ret = bdrv_append(top, source, errp);
     if (ret < 0) {
-        error_prepend(errp, "Cannot append backup-top filter: ");
+        error_prepend(errp, "Cannot append copy-before-write filter: ");
         goto fail;
     }
     appended = true;
@@ -231,7 +231,7 @@ BlockDriverState *bdrv_backup_top_append(BlockDriverState *source,
 
 fail:
     if (appended) {
-        bdrv_backup_top_drop(top);
+        bdrv_cbw_drop(top);
     } else {
         bdrv_unref(top);
     }
@@ -241,9 +241,9 @@ fail:
     return NULL;
 }
 
-void bdrv_backup_top_drop(BlockDriverState *bs)
+void bdrv_cbw_drop(BlockDriverState *bs)
 {
-    BDRVBackupTopState *s = bs->opaque;
+    BDRVCopyBeforeWriteState *s = bs->opaque;
 
     bdrv_drop_filter(bs, &error_abort);
 
diff --git a/MAINTAINERS b/MAINTAINERS
index 37b1a8e442..af8aafd06d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2337,8 +2337,8 @@ F: block/mirror.c
 F: qapi/job.json
 F: block/block-copy.c
 F: include/block/block-copy.c
-F: block/backup-top.h
-F: block/backup-top.c
+F: block/copy-before-write.h
+F: block/copy-before-write.c
 F: include/block/aio_task.h
 F: block/aio_task.c
 F: util/qemu-co-shared-resource.c
diff --git a/block/meson.build b/block/meson.build
index 0450914c7a..66ee11e62c 100644
--- a/block/meson.build
+++ b/block/meson.build
@@ -4,7 +4,7 @@ block_ss.add(files(
   'aio_task.c',
   'amend.c',
   'backup.c',
-  'backup-top.c',
+  'copy-before-write.c',
   'blkdebug.c',
   'blklogwrites.c',
   'blkverify.c',
diff --git a/tests/qemu-iotests/283 b/tests/qemu-iotests/283
index 010c22f0a2..a09e0183ae 100755
--- a/tests/qemu-iotests/283
+++ b/tests/qemu-iotests/283
@@ -1,7 +1,7 @@
 #!/usr/bin/env python3
 # group: auto quick
 #
-# Test for backup-top filter permission activation failure
+# Test for copy-before-write filter permission conflict
 #
 # Copyright (c) 2019 Virtuozzo International GmbH.
 #
@@ -31,13 +31,13 @@ size = 1024 * 1024
 """ Test description
 
 When performing a backup, all writes on the source subtree must go through the
-backup-top filter so it can copy all data to the target before it is changed.
-backup-top filter is appended above source node, to achieve this thing, so all
-parents of source node are handled. A configuration with side parents of source
-sub-tree with write permission is unsupported (we'd have append several
-backup-top filter like nodes to handle such parents). The test create an
-example of such configuration and checks that a backup is then not allowed
-(blockdev-backup command should fail).
+copy-before-write filter so it can copy all data to the target before it is
+changed.  copy-before-write filter is appended above source node, to achieve
+this thing, so all parents of source node are handled. A configuration with
+side parents of source sub-tree with write permission is unsupported (we'd have
+append several copy-before-write filter like nodes to handle such parents). The
+test create an example of such configuration and checks that a backup is then
+not allowed (blockdev-backup command should fail).
 
 The configuration:
 
@@ -57,11 +57,10 @@ The configuration:
                         │    base     │ ◀──────────── │ other │
                         └─────────────┘               └───────┘
 
-On activation (see .active field of backup-top state in block/backup-top.c),
-backup-top is going to unshare write permission on its source child. Write
-unsharing will be propagated to the "source->base" link and will conflict with
-other node write permission. So permission update will fail and backup job will
-not be started.
+copy-before-write filter wants to unshare write permission on its source child.
+Write unsharing will be propagated to the "source->base" link and will conflict
+with other node write permission. So permission update will fail and backup job
+will not be started.
 
 Note, that the only thing which prevents backup of running on such
 configuration is default permission propagation scheme. It may be altered by
@@ -99,13 +98,9 @@ vm.qmp_log('blockdev-backup', sync='full', device='source', target='target')
 vm.shutdown()
 
 
-print('\n=== backup-top should be gone after job-finalize ===\n')
+print('\n=== copy-before-write filter should be gone after job-finalize ===\n')
 
-# Check that the backup-top node is gone after job-finalize.
-#
-# During finalization, the node becomes inactive and can no longer
-# function.  If it is still present, new parents might be attached, and
-# there would be no meaningful way to handle their I/O requests.
+# Check that the copy-before-write node is gone after job-finalize.
 
 vm = iotests.VM()
 vm.launch()
@@ -131,7 +126,7 @@ vm.qmp_log('blockdev-backup',
 
 vm.event_wait('BLOCK_JOB_PENDING', 5.0)
 
-# The backup-top filter should still be present prior to finalization
+# The copy-before-write filter should still be present prior to finalization
 assert vm.node_info('backup-filter') is not None
 
 vm.qmp_log('job-finalize', id='backup')
diff --git a/tests/qemu-iotests/283.out b/tests/qemu-iotests/283.out
index c6e12b15c5..f2b7219632 100644
--- a/tests/qemu-iotests/283.out
+++ b/tests/qemu-iotests/283.out
@@ -5,9 +5,9 @@
 {"execute": "blockdev-add", "arguments": {"driver": "blkdebug", "image": "base", "node-name": "other", "take-child-perms": ["write"]}}
 {"return": {}}
 {"execute": "blockdev-backup", "arguments": {"device": "source", "sync": "full", "target": "target"}}
-{"error": {"class": "GenericError", "desc": "Cannot append backup-top filter: Permission conflict on node 'base': permissions 'write' are both required by node 'other' (uses node 'base' as 'image' child) and unshared by node 'source' (uses node 'base' as 'image' child)."}}
+{"error": {"class": "GenericError", "desc": "Cannot append copy-before-write filter: Permission conflict on node 'base': permissions 'write' are both required by node 'other' (uses node 'base' as 'image' child) and unshared by node 'source' (uses node 'base' as 'image' child)."}}
 
-=== backup-top should be gone after job-finalize ===
+=== copy-before-write filter should be gone after job-finalize ===
 
 {"execute": "blockdev-add", "arguments": {"driver": "null-co", "node-name": "source"}}
 {"return": {}}
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 06/33] block-copy: move detecting fleecing scheme to block-copy
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (4 preceding siblings ...)
  2021-08-04  9:37 ` [PATCH v7 05/33] block: rename backup-top to copy-before-write Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:37 ` Vladimir Sementsov-Ogievskiy
  2021-08-10 14:44   ` Hanna Reitz
  2021-08-04  9:37 ` [PATCH v7 07/33] block/block-copy: introduce block_copy_set_copy_opts() Vladimir Sementsov-Ogievskiy
                   ` (26 subsequent siblings)
  32 siblings, 1 reply; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:37 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

We want to simplify initialization interface of copy-before-write
filter as we are going to make it public. So, let's detect fleecing
scheme exactly in block-copy code, to not pass this information through
extra levels.

Why not just set BDRV_REQ_SERIALISING unconditionally: because we are
going to implement new more efficient fleecing scheme which will not
rely on backing feature.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 block/copy-before-write.h  |  2 +-
 include/block/block-copy.h |  3 +--
 block/backup.c             | 21 +--------------------
 block/block-copy.c         | 24 +++++++++++++++++++++---
 block/copy-before-write.c  |  4 ++--
 5 files changed, 26 insertions(+), 28 deletions(-)

diff --git a/block/copy-before-write.h b/block/copy-before-write.h
index 5977b7aa31..f37e2249ae 100644
--- a/block/copy-before-write.h
+++ b/block/copy-before-write.h
@@ -34,7 +34,7 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
                                   const char *filter_node_name,
                                   uint64_t cluster_size,
                                   BackupPerf *perf,
-                                  BdrvRequestFlags write_flags,
+                                  bool compress,
                                   BlockCopyState **bcs,
                                   Error **errp);
 void bdrv_cbw_drop(BlockDriverState *bs);
diff --git a/include/block/block-copy.h b/include/block/block-copy.h
index 5c8278895c..734389d32a 100644
--- a/include/block/block-copy.h
+++ b/include/block/block-copy.h
@@ -26,8 +26,7 @@ typedef struct BlockCopyCallState BlockCopyCallState;
 
 BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
                                      int64_t cluster_size, bool use_copy_range,
-                                     BdrvRequestFlags write_flags,
-                                     Error **errp);
+                                     bool compress, Error **errp);
 
 void block_copy_set_progress_meter(BlockCopyState *s, ProgressMeter *pm);
 
diff --git a/block/backup.c b/block/backup.c
index ac91821b08..84f9a5f02c 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -407,7 +407,6 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
     int64_t len, target_len;
     BackupBlockJob *job = NULL;
     int64_t cluster_size;
-    BdrvRequestFlags write_flags;
     BlockDriverState *cbw = NULL;
     BlockCopyState *bcs = NULL;
 
@@ -504,26 +503,8 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
         goto error;
     }
 
-    /*
-     * 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
-     * source at backup-start point in time. And target is going to be read by
-     * somebody (for example, used as NBD export) during backup job.
-     *
-     * In this case, we need to add BDRV_REQ_SERIALISING write flag to avoid
-     * intersection of backup writes and third party reads from target,
-     * otherwise reading from target we may occasionally read already updated by
-     * guest data.
-     *
-     * For more information see commit f8d59dfb40bb and test
-     * tests/qemu-iotests/222
-     */
-    write_flags = (bdrv_chain_contains(target, bs) ? BDRV_REQ_SERIALISING : 0) |
-                  (compress ? BDRV_REQ_WRITE_COMPRESSED : 0),
-
     cbw = bdrv_cbw_append(bs, target, filter_node_name,
-                                        cluster_size, perf,
-                                        write_flags, &bcs, errp);
+                          cluster_size, perf, compress, &bcs, errp);
     if (!cbw) {
         goto error;
     }
diff --git a/block/block-copy.c b/block/block-copy.c
index 0becad52da..58b4345a5a 100644
--- a/block/block-copy.c
+++ b/block/block-copy.c
@@ -317,10 +317,11 @@ static uint32_t block_copy_max_transfer(BdrvChild *source, BdrvChild *target)
 
 BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
                                      int64_t cluster_size, bool use_copy_range,
-                                     BdrvRequestFlags write_flags, Error **errp)
+                                     bool compress, Error **errp)
 {
     BlockCopyState *s;
     BdrvDirtyBitmap *copy_bitmap;
+    bool is_fleecing;
 
     copy_bitmap = bdrv_create_dirty_bitmap(source->bs, cluster_size, NULL,
                                            errp);
@@ -329,6 +330,22 @@ BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
     }
     bdrv_disable_dirty_bitmap(copy_bitmap);
 
+    /*
+     * 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
+     * source at backup-start point in time. And target is going to be read by
+     * somebody (for example, used as NBD export) during backup job.
+     *
+     * In this case, we need to add BDRV_REQ_SERIALISING write flag to avoid
+     * intersection of backup writes and third party reads from target,
+     * otherwise reading from target we may occasionally read already updated by
+     * guest data.
+     *
+     * For more information see commit f8d59dfb40bb and test
+     * tests/qemu-iotests/222
+     */
+    is_fleecing = bdrv_chain_contains(target->bs, source->bs);
+
     s = g_new(BlockCopyState, 1);
     *s = (BlockCopyState) {
         .source = source,
@@ -336,7 +353,8 @@ BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
         .copy_bitmap = copy_bitmap,
         .cluster_size = cluster_size,
         .len = bdrv_dirty_bitmap_size(copy_bitmap),
-        .write_flags = write_flags,
+        .write_flags = (is_fleecing ? BDRV_REQ_SERIALISING : 0) |
+            (compress ? BDRV_REQ_WRITE_COMPRESSED : 0),
         .mem = shres_create(BLOCK_COPY_MAX_MEM),
         .max_transfer = QEMU_ALIGN_DOWN(
                                     block_copy_max_transfer(source, target),
@@ -351,7 +369,7 @@ BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
          * behalf).
          */
         s->method = COPY_READ_WRITE_CLUSTER;
-    } else if (write_flags & BDRV_REQ_WRITE_COMPRESSED) {
+    } else if (compress) {
         /* Compression supports only cluster-size writes and no copy-range. */
         s->method = COPY_READ_WRITE_CLUSTER;
     } else {
diff --git a/block/copy-before-write.c b/block/copy-before-write.c
index 0dc5a107cf..4337076c1c 100644
--- a/block/copy-before-write.c
+++ b/block/copy-before-write.c
@@ -171,7 +171,7 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
                                   const char *filter_node_name,
                                   uint64_t cluster_size,
                                   BackupPerf *perf,
-                                  BdrvRequestFlags write_flags,
+                                  bool compress,
                                   BlockCopyState **bcs,
                                   Error **errp)
 {
@@ -218,7 +218,7 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
     state->cluster_size = cluster_size;
     state->bcs = block_copy_state_new(top->backing, state->target,
                                       cluster_size, perf->use_copy_range,
-                                      write_flags, errp);
+                                      compress, errp);
     if (!state->bcs) {
         error_prepend(errp, "Cannot create block-copy-state: ");
         goto fail;
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 07/33] block/block-copy: introduce block_copy_set_copy_opts()
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (5 preceding siblings ...)
  2021-08-04  9:37 ` [PATCH v7 06/33] block-copy: move detecting fleecing scheme to block-copy Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:37 ` Vladimir Sementsov-Ogievskiy
  2021-08-10 14:55   ` Hanna Reitz
  2021-08-04  9:37 ` [PATCH v7 08/33] block/backup: set copy_range and compress after filter insertion Vladimir Sementsov-Ogievskiy
                   ` (25 subsequent siblings)
  32 siblings, 1 reply; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:37 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

We'll need a possibility to set compress and use_copy_range options
after initialization of the state. So make corresponding part of
block_copy_state_new() separate and public.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 include/block/block-copy.h |  2 ++
 block/block-copy.c         | 66 +++++++++++++++++++++-----------------
 2 files changed, 39 insertions(+), 29 deletions(-)

diff --git a/include/block/block-copy.h b/include/block/block-copy.h
index 734389d32a..f0ba7bc828 100644
--- a/include/block/block-copy.h
+++ b/include/block/block-copy.h
@@ -28,6 +28,8 @@ BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
                                      int64_t cluster_size, bool use_copy_range,
                                      bool compress, Error **errp);
 
+void block_copy_set_copy_opts(BlockCopyState *s, bool use_copy_range,
+                              bool compress);
 void block_copy_set_progress_meter(BlockCopyState *s, ProgressMeter *pm);
 
 void block_copy_state_free(BlockCopyState *s);
diff --git a/block/block-copy.c b/block/block-copy.c
index 58b4345a5a..84c29fb233 100644
--- a/block/block-copy.c
+++ b/block/block-copy.c
@@ -315,21 +315,11 @@ static uint32_t block_copy_max_transfer(BdrvChild *source, BdrvChild *target)
                                      target->bs->bl.max_transfer));
 }
 
-BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
-                                     int64_t cluster_size, bool use_copy_range,
-                                     bool compress, Error **errp)
+/* Function should be called prior any actual copy request */
+void block_copy_set_copy_opts(BlockCopyState *s, bool use_copy_range,
+                              bool compress)
 {
-    BlockCopyState *s;
-    BdrvDirtyBitmap *copy_bitmap;
     bool is_fleecing;
-
-    copy_bitmap = bdrv_create_dirty_bitmap(source->bs, cluster_size, NULL,
-                                           errp);
-    if (!copy_bitmap) {
-        return NULL;
-    }
-    bdrv_disable_dirty_bitmap(copy_bitmap);
-
     /*
      * 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
@@ -344,24 +334,12 @@ BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
      * For more information see commit f8d59dfb40bb and test
      * tests/qemu-iotests/222
      */
-    is_fleecing = bdrv_chain_contains(target->bs, source->bs);
+    is_fleecing = bdrv_chain_contains(s->target->bs, s->source->bs);
 
-    s = g_new(BlockCopyState, 1);
-    *s = (BlockCopyState) {
-        .source = source,
-        .target = target,
-        .copy_bitmap = copy_bitmap,
-        .cluster_size = cluster_size,
-        .len = bdrv_dirty_bitmap_size(copy_bitmap),
-        .write_flags = (is_fleecing ? BDRV_REQ_SERIALISING : 0) |
-            (compress ? BDRV_REQ_WRITE_COMPRESSED : 0),
-        .mem = shres_create(BLOCK_COPY_MAX_MEM),
-        .max_transfer = QEMU_ALIGN_DOWN(
-                                    block_copy_max_transfer(source, target),
-                                    cluster_size),
-    };
+    s->write_flags = (is_fleecing ? BDRV_REQ_SERIALISING : 0) |
+        (compress ? BDRV_REQ_WRITE_COMPRESSED : 0);
 
-    if (s->max_transfer < cluster_size) {
+    if (s->max_transfer < s->cluster_size) {
         /*
          * copy_range does not respect max_transfer. We don't want to bother
          * with requests smaller than block-copy cluster size, so fallback to
@@ -379,6 +357,36 @@ BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
          */
         s->method = use_copy_range ? COPY_RANGE_SMALL : COPY_READ_WRITE;
     }
+}
+
+BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
+                                     int64_t cluster_size, bool use_copy_range,
+                                     bool compress, Error **errp)
+{
+    BlockCopyState *s;
+    BdrvDirtyBitmap *copy_bitmap;
+
+    copy_bitmap = bdrv_create_dirty_bitmap(source->bs, cluster_size, NULL,
+                                           errp);
+    if (!copy_bitmap) {
+        return NULL;
+    }
+    bdrv_disable_dirty_bitmap(copy_bitmap);
+
+    s = g_new(BlockCopyState, 1);
+    *s = (BlockCopyState) {
+        .source = source,
+        .target = target,
+        .copy_bitmap = copy_bitmap,
+        .cluster_size = cluster_size,
+        .len = bdrv_dirty_bitmap_size(copy_bitmap),
+        .mem = shres_create(BLOCK_COPY_MAX_MEM),
+        .max_transfer = QEMU_ALIGN_DOWN(
+                                    block_copy_max_transfer(source, target),
+                                    cluster_size),
+    };
+
+    block_copy_set_copy_opts(s, use_copy_range, compress);
 
     ratelimit_init(&s->rate_limit);
     qemu_co_mutex_init(&s->lock);
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 08/33] block/backup: set copy_range and compress after filter insertion
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (6 preceding siblings ...)
  2021-08-04  9:37 ` [PATCH v7 07/33] block/block-copy: introduce block_copy_set_copy_opts() Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:37 ` Vladimir Sementsov-Ogievskiy
  2021-08-10 15:07   ` Hanna Reitz
  2021-08-04  9:37 ` [PATCH v7 09/33] block/backup: move cluster size calculation to block-copy Vladimir Sementsov-Ogievskiy
                   ` (24 subsequent siblings)
  32 siblings, 1 reply; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:37 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

We are going to publish copy-before-write filter, so it would be
initialized through options. Still we don't want to publish compress
and copy-range options, as

1. Modern way to enable compression is to use compress filter.

2. For copy-range it's unclean how to make proper interface:
 - it's has experimental prefix for backup job anyway
 - the whole BackupPerf structure doesn't make sense for the filter
 So, let's just add copy-range possibility to the filter later if
 needed.

Still, we are going to continue support for compression and
experimental copy-range in backup job. So, set these options after
filter creation.

Note, that we can drop "compress" argument of bdrv_cbw_append() now, as
well as "perf". The only reason not doing so is that now, when I
prepare this patch the big series around it is already reviewed and I
want to avoid extra rebase conflicts to simplify review of the
following version.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 block/copy-before-write.h | 1 -
 block/backup.c            | 3 ++-
 block/copy-before-write.c | 4 +---
 3 files changed, 3 insertions(+), 5 deletions(-)

diff --git a/block/copy-before-write.h b/block/copy-before-write.h
index f37e2249ae..538aab8bdb 100644
--- a/block/copy-before-write.h
+++ b/block/copy-before-write.h
@@ -33,7 +33,6 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
                                   BlockDriverState *target,
                                   const char *filter_node_name,
                                   uint64_t cluster_size,
-                                  BackupPerf *perf,
                                   bool compress,
                                   BlockCopyState **bcs,
                                   Error **errp);
diff --git a/block/backup.c b/block/backup.c
index 84f9a5f02c..b31fd99ab3 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -504,7 +504,7 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
     }
 
     cbw = bdrv_cbw_append(bs, target, filter_node_name,
-                          cluster_size, perf, compress, &bcs, errp);
+                          cluster_size, false, &bcs, errp);
     if (!cbw) {
         goto error;
     }
@@ -530,6 +530,7 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
     job->len = len;
     job->perf = *perf;
 
+    block_copy_set_copy_opts(bcs, perf->use_copy_range, compress);
     block_copy_set_progress_meter(bcs, &job->common.job.progress);
     block_copy_set_speed(bcs, speed);
 
diff --git a/block/copy-before-write.c b/block/copy-before-write.c
index 4337076c1c..235251a640 100644
--- a/block/copy-before-write.c
+++ b/block/copy-before-write.c
@@ -170,7 +170,6 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
                                   BlockDriverState *target,
                                   const char *filter_node_name,
                                   uint64_t cluster_size,
-                                  BackupPerf *perf,
                                   bool compress,
                                   BlockCopyState **bcs,
                                   Error **errp)
@@ -217,8 +216,7 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
 
     state->cluster_size = cluster_size;
     state->bcs = block_copy_state_new(top->backing, state->target,
-                                      cluster_size, perf->use_copy_range,
-                                      compress, errp);
+                                      cluster_size, false, compress, errp);
     if (!state->bcs) {
         error_prepend(errp, "Cannot create block-copy-state: ");
         goto fail;
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 09/33] block/backup: move cluster size calculation to block-copy
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (7 preceding siblings ...)
  2021-08-04  9:37 ` [PATCH v7 08/33] block/backup: set copy_range and compress after filter insertion Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:37 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:37 ` [PATCH v7 10/33] block/copy-before-write: relax permission requirements when no parents Vladimir Sementsov-Ogievskiy
                   ` (23 subsequent siblings)
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:37 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

The main consumer of cluster-size is block-copy. Let's calculate it
here instead of passing through backup-top.

We are going to publish copy-before-write filter soon, so it will be
created through options. But we don't want for now to make explicit
option for cluster-size, let's continue to calculate it automatically.
So, now is the time to get rid of cluster_size argument for
bdrv_cbw_append().

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 block/copy-before-write.h  |  1 -
 include/block/block-copy.h |  5 +--
 block/backup.c             | 62 ++++++--------------------------------
 block/block-copy.c         | 51 ++++++++++++++++++++++++++++++-
 block/copy-before-write.c  | 10 +++---
 5 files changed, 66 insertions(+), 63 deletions(-)

diff --git a/block/copy-before-write.h b/block/copy-before-write.h
index 538aab8bdb..b386fd8f01 100644
--- a/block/copy-before-write.h
+++ b/block/copy-before-write.h
@@ -32,7 +32,6 @@
 BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
                                   BlockDriverState *target,
                                   const char *filter_node_name,
-                                  uint64_t cluster_size,
                                   bool compress,
                                   BlockCopyState **bcs,
                                   Error **errp);
diff --git a/include/block/block-copy.h b/include/block/block-copy.h
index f0ba7bc828..9c24e8f38e 100644
--- a/include/block/block-copy.h
+++ b/include/block/block-copy.h
@@ -25,8 +25,8 @@ typedef struct BlockCopyState BlockCopyState;
 typedef struct BlockCopyCallState BlockCopyCallState;
 
 BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
-                                     int64_t cluster_size, bool use_copy_range,
-                                     bool compress, Error **errp);
+                                     bool use_copy_range, bool compress,
+                                     Error **errp);
 
 void block_copy_set_copy_opts(BlockCopyState *s, bool use_copy_range,
                               bool compress);
@@ -90,6 +90,7 @@ void block_copy_kick(BlockCopyCallState *call_state);
 void block_copy_call_cancel(BlockCopyCallState *call_state);
 
 BdrvDirtyBitmap *block_copy_dirty_bitmap(BlockCopyState *s);
+int64_t block_copy_cluster_size(BlockCopyState *s);
 void block_copy_set_skip_unallocated(BlockCopyState *s, bool skip);
 
 #endif /* BLOCK_COPY_H */
diff --git a/block/backup.c b/block/backup.c
index b31fd99ab3..83516297cb 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -29,8 +29,6 @@
 
 #include "block/copy-before-write.h"
 
-#define BACKUP_CLUSTER_SIZE_DEFAULT (1 << 16)
-
 typedef struct BackupBlockJob {
     BlockJob common;
     BlockDriverState *cbw;
@@ -354,43 +352,6 @@ static const BlockJobDriver backup_job_driver = {
     .set_speed = backup_set_speed,
 };
 
-static int64_t backup_calculate_cluster_size(BlockDriverState *target,
-                                             Error **errp)
-{
-    int ret;
-    BlockDriverInfo bdi;
-    bool target_does_cow = bdrv_backing_chain_next(target);
-
-    /*
-     * If there is no backing file on the target, we cannot rely on COW if our
-     * backup cluster size is smaller than the target cluster size. Even for
-     * targets with a backing file, try to avoid COW if possible.
-     */
-    ret = bdrv_get_info(target, &bdi);
-    if (ret == -ENOTSUP && !target_does_cow) {
-        /* Cluster size is not defined */
-        warn_report("The target block device doesn't provide "
-                    "information about the block size and it doesn't have a "
-                    "backing file. The default block size of %u bytes is "
-                    "used. If the actual block size of the target exceeds "
-                    "this default, the backup may be unusable",
-                    BACKUP_CLUSTER_SIZE_DEFAULT);
-        return BACKUP_CLUSTER_SIZE_DEFAULT;
-    } else if (ret < 0 && !target_does_cow) {
-        error_setg_errno(errp, -ret,
-            "Couldn't determine the cluster size of the target image, "
-            "which has no backing file");
-        error_append_hint(errp,
-            "Aborting, since this may create an unusable destination image\n");
-        return ret;
-    } else if (ret < 0 && target_does_cow) {
-        /* Not fatal; just trudge on ahead. */
-        return BACKUP_CLUSTER_SIZE_DEFAULT;
-    }
-
-    return MAX(BACKUP_CLUSTER_SIZE_DEFAULT, bdi.cluster_size);
-}
-
 BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
                   BlockDriverState *target, int64_t speed,
                   MirrorSyncMode sync_mode, BdrvDirtyBitmap *sync_bitmap,
@@ -448,11 +409,6 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
         return NULL;
     }
 
-    cluster_size = backup_calculate_cluster_size(target, errp);
-    if (cluster_size < 0) {
-        goto error;
-    }
-
     if (perf->max_workers < 1) {
         error_setg(errp, "max-workers must be greater than zero");
         return NULL;
@@ -464,13 +420,6 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
         return NULL;
     }
 
-    if (perf->max_chunk && perf->max_chunk < cluster_size) {
-        error_setg(errp, "Required max-chunk (%" PRIi64 ") is less than backup "
-                   "cluster size (%" PRIi64 ")", perf->max_chunk, cluster_size);
-        return NULL;
-    }
-
-
     if (sync_bitmap) {
         /* If we need to write to this bitmap, check that we can: */
         if (bitmap_mode != BITMAP_SYNC_MODE_NEVER &&
@@ -503,12 +452,19 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
         goto error;
     }
 
-    cbw = bdrv_cbw_append(bs, target, filter_node_name,
-                          cluster_size, false, &bcs, errp);
+    cbw = bdrv_cbw_append(bs, target, filter_node_name, false, &bcs, errp);
     if (!cbw) {
         goto error;
     }
 
+    cluster_size = block_copy_cluster_size(bcs);
+
+    if (perf->max_chunk && perf->max_chunk < cluster_size) {
+        error_setg(errp, "Required max-chunk (%" PRIi64 ") is less than backup "
+                   "cluster size (%" PRIi64 ")", perf->max_chunk, cluster_size);
+        goto error;
+    }
+
     /* job->len is fixed, so we can't allow resize */
     job = block_job_create(job_id, &backup_job_driver, txn, cbw,
                            0, BLK_PERM_ALL,
diff --git a/block/block-copy.c b/block/block-copy.c
index 84c29fb233..78ee255fd0 100644
--- a/block/block-copy.c
+++ b/block/block-copy.c
@@ -27,6 +27,7 @@
 #define BLOCK_COPY_MAX_MEM (128 * MiB)
 #define BLOCK_COPY_MAX_WORKERS 64
 #define BLOCK_COPY_SLICE_TIME 100000000ULL /* ns */
+#define BLOCK_COPY_CLUSTER_SIZE_DEFAULT (1 << 16)
 
 typedef enum {
     COPY_READ_WRITE_CLUSTER,
@@ -359,13 +360,56 @@ void block_copy_set_copy_opts(BlockCopyState *s, bool use_copy_range,
     }
 }
 
+static int64_t block_copy_calculate_cluster_size(BlockDriverState *target,
+                                                 Error **errp)
+{
+    int ret;
+    BlockDriverInfo bdi;
+    bool target_does_cow = bdrv_backing_chain_next(target);
+
+    /*
+     * If there is no backing file on the target, we cannot rely on COW if our
+     * backup cluster size is smaller than the target cluster size. Even for
+     * targets with a backing file, try to avoid COW if possible.
+     */
+    ret = bdrv_get_info(target, &bdi);
+    if (ret == -ENOTSUP && !target_does_cow) {
+        /* Cluster size is not defined */
+        warn_report("The target block device doesn't provide "
+                    "information about the block size and it doesn't have a "
+                    "backing file. The default block size of %u bytes is "
+                    "used. If the actual block size of the target exceeds "
+                    "this default, the backup may be unusable",
+                    BLOCK_COPY_CLUSTER_SIZE_DEFAULT);
+        return BLOCK_COPY_CLUSTER_SIZE_DEFAULT;
+    } else if (ret < 0 && !target_does_cow) {
+        error_setg_errno(errp, -ret,
+            "Couldn't determine the cluster size of the target image, "
+            "which has no backing file");
+        error_append_hint(errp,
+            "Aborting, since this may create an unusable destination image\n");
+        return ret;
+    } else if (ret < 0 && target_does_cow) {
+        /* Not fatal; just trudge on ahead. */
+        return BLOCK_COPY_CLUSTER_SIZE_DEFAULT;
+    }
+
+    return MAX(BLOCK_COPY_CLUSTER_SIZE_DEFAULT, bdi.cluster_size);
+}
+
 BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
-                                     int64_t cluster_size, bool use_copy_range,
+                                     bool use_copy_range,
                                      bool compress, Error **errp)
 {
     BlockCopyState *s;
+    int64_t cluster_size;
     BdrvDirtyBitmap *copy_bitmap;
 
+    cluster_size = block_copy_calculate_cluster_size(target->bs, errp);
+    if (cluster_size < 0) {
+        return NULL;
+    }
+
     copy_bitmap = bdrv_create_dirty_bitmap(source->bs, cluster_size, NULL,
                                            errp);
     if (!copy_bitmap) {
@@ -959,6 +1003,11 @@ BdrvDirtyBitmap *block_copy_dirty_bitmap(BlockCopyState *s)
     return s->copy_bitmap;
 }
 
+int64_t block_copy_cluster_size(BlockCopyState *s)
+{
+    return s->cluster_size;
+}
+
 void block_copy_set_skip_unallocated(BlockCopyState *s, bool skip)
 {
     qatomic_set(&s->skip_unallocated, skip);
diff --git a/block/copy-before-write.c b/block/copy-before-write.c
index 235251a640..a7996d54db 100644
--- a/block/copy-before-write.c
+++ b/block/copy-before-write.c
@@ -37,7 +37,6 @@
 typedef struct BDRVCopyBeforeWriteState {
     BlockCopyState *bcs;
     BdrvChild *target;
-    int64_t cluster_size;
 } BDRVCopyBeforeWriteState;
 
 static coroutine_fn int cbw_co_preadv(
@@ -52,13 +51,14 @@ static coroutine_fn int cbw_do_copy_before_write(BlockDriverState *bs,
 {
     BDRVCopyBeforeWriteState *s = bs->opaque;
     uint64_t off, end;
+    int64_t cluster_size = block_copy_cluster_size(s->bcs);
 
     if (flags & BDRV_REQ_WRITE_UNCHANGED) {
         return 0;
     }
 
-    off = QEMU_ALIGN_DOWN(offset, s->cluster_size);
-    end = QEMU_ALIGN_UP(offset + bytes, s->cluster_size);
+    off = QEMU_ALIGN_DOWN(offset, cluster_size);
+    end = QEMU_ALIGN_UP(offset + bytes, cluster_size);
 
     return block_copy(s->bcs, off, end - off, true);
 }
@@ -169,7 +169,6 @@ BlockDriver bdrv_cbw_filter = {
 BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
                                   BlockDriverState *target,
                                   const char *filter_node_name,
-                                  uint64_t cluster_size,
                                   bool compress,
                                   BlockCopyState **bcs,
                                   Error **errp)
@@ -214,9 +213,8 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
     }
     appended = true;
 
-    state->cluster_size = cluster_size;
     state->bcs = block_copy_state_new(top->backing, state->target,
-                                      cluster_size, false, compress, errp);
+                                      false, compress, errp);
     if (!state->bcs) {
         error_prepend(errp, "Cannot create block-copy-state: ");
         goto fail;
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 10/33] block/copy-before-write: relax permission requirements when no parents
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (8 preceding siblings ...)
  2021-08-04  9:37 ` [PATCH v7 09/33] block/backup: move cluster size calculation to block-copy Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:37 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:37 ` [PATCH v7 11/33] block/copy-before-write: drop extra bdrv_unref on failure path Vladimir Sementsov-Ogievskiy
                   ` (22 subsequent siblings)
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:37 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

We are going to publish copy-before-write filter. So, user should be
able to create it with blockdev-add first, specifying both filtered and
target children. And then do blockdev-reopen, to actually insert the
filter where needed.

Currently, filter unshares write permission unconditionally on source
node. It's good, but it will not allow to do blockdev-add. So, let's
relax restrictions when filter doesn't have any parent.

Test output is modified, as now permission conflict happens only when
job creates a blk parent for filter node.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 block/copy-before-write.c  | 8 +++++---
 tests/qemu-iotests/283.out | 2 +-
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/block/copy-before-write.c b/block/copy-before-write.c
index a7996d54db..2a51cc64e4 100644
--- a/block/copy-before-write.c
+++ b/block/copy-before-write.c
@@ -142,10 +142,12 @@ static void cbw_child_perm(BlockDriverState *bs, BdrvChild *c,
         bdrv_default_perms(bs, c, role, reopen_queue,
                            perm, shared, nperm, nshared);
 
-        if (perm & BLK_PERM_WRITE) {
-            *nperm = *nperm | BLK_PERM_CONSISTENT_READ;
+        if (!QLIST_EMPTY(&bs->parents)) {
+            if (perm & BLK_PERM_WRITE) {
+                *nperm = *nperm | BLK_PERM_CONSISTENT_READ;
+            }
+            *nshared &= ~(BLK_PERM_WRITE | BLK_PERM_RESIZE);
         }
-        *nshared &= ~(BLK_PERM_WRITE | BLK_PERM_RESIZE);
     }
 }
 
diff --git a/tests/qemu-iotests/283.out b/tests/qemu-iotests/283.out
index f2b7219632..5bb75952ef 100644
--- a/tests/qemu-iotests/283.out
+++ b/tests/qemu-iotests/283.out
@@ -5,7 +5,7 @@
 {"execute": "blockdev-add", "arguments": {"driver": "blkdebug", "image": "base", "node-name": "other", "take-child-perms": ["write"]}}
 {"return": {}}
 {"execute": "blockdev-backup", "arguments": {"device": "source", "sync": "full", "target": "target"}}
-{"error": {"class": "GenericError", "desc": "Cannot append copy-before-write filter: Permission conflict on node 'base': permissions 'write' are both required by node 'other' (uses node 'base' as 'image' child) and unshared by node 'source' (uses node 'base' as 'image' child)."}}
+{"error": {"class": "GenericError", "desc": "Permission conflict on node 'base': permissions 'write' are both required by node 'other' (uses node 'base' as 'image' child) and unshared by node 'source' (uses node 'base' as 'image' child)."}}
 
 === copy-before-write filter should be gone after job-finalize ===
 
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 11/33] block/copy-before-write: drop extra bdrv_unref on failure path
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (9 preceding siblings ...)
  2021-08-04  9:37 ` [PATCH v7 10/33] block/copy-before-write: relax permission requirements when no parents Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:37 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:37 ` [PATCH v7 12/33] block/copy-before-write: use file child instead of backing Vladimir Sementsov-Ogievskiy
                   ` (21 subsequent siblings)
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:37 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

bdrv_attach_child() do bdrv_unref() on failure, so we shouldn't do it
by hand here.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 block/copy-before-write.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/block/copy-before-write.c b/block/copy-before-write.c
index 2a51cc64e4..945d9340f4 100644
--- a/block/copy-before-write.c
+++ b/block/copy-before-write.c
@@ -201,7 +201,6 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
     state->target = bdrv_attach_child(top, target, "target", &child_of_bds,
                                       BDRV_CHILD_DATA, errp);
     if (!state->target) {
-        bdrv_unref(target);
         bdrv_unref(top);
         return NULL;
     }
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 12/33] block/copy-before-write: use file child instead of backing
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (10 preceding siblings ...)
  2021-08-04  9:37 ` [PATCH v7 11/33] block/copy-before-write: drop extra bdrv_unref on failure path Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:37 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:37 ` [PATCH v7 13/33] block/copy-before-write: bdrv_cbw_append(): replace child at last Vladimir Sementsov-Ogievskiy
                   ` (20 subsequent siblings)
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:37 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

We are going to publish copy-before-write filter, and there no public
backing-child-based filter in Qemu. No reason to create a precedent, so
let's refactor copy-before-write filter instead.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 block/copy-before-write.c | 39 ++++++++++++++++++++++-----------------
 1 file changed, 22 insertions(+), 17 deletions(-)

diff --git a/block/copy-before-write.c b/block/copy-before-write.c
index 945d9340f4..7a6c15f141 100644
--- a/block/copy-before-write.c
+++ b/block/copy-before-write.c
@@ -43,7 +43,7 @@ static coroutine_fn int cbw_co_preadv(
         BlockDriverState *bs, uint64_t offset, uint64_t bytes,
         QEMUIOVector *qiov, int flags)
 {
-    return bdrv_co_preadv(bs->backing, offset, bytes, qiov, flags);
+    return bdrv_co_preadv(bs->file, offset, bytes, qiov, flags);
 }
 
 static coroutine_fn int cbw_do_copy_before_write(BlockDriverState *bs,
@@ -71,7 +71,7 @@ static int coroutine_fn cbw_co_pdiscard(BlockDriverState *bs,
         return ret;
     }
 
-    return bdrv_co_pdiscard(bs->backing, offset, bytes);
+    return bdrv_co_pdiscard(bs->file, offset, bytes);
 }
 
 static int coroutine_fn cbw_co_pwrite_zeroes(BlockDriverState *bs,
@@ -82,7 +82,7 @@ static int coroutine_fn cbw_co_pwrite_zeroes(BlockDriverState *bs,
         return ret;
     }
 
-    return bdrv_co_pwrite_zeroes(bs->backing, offset, bytes, flags);
+    return bdrv_co_pwrite_zeroes(bs->file, offset, bytes, flags);
 }
 
 static coroutine_fn int cbw_co_pwritev(BlockDriverState *bs,
@@ -95,29 +95,22 @@ static coroutine_fn int cbw_co_pwritev(BlockDriverState *bs,
         return ret;
     }
 
-    return bdrv_co_pwritev(bs->backing, offset, bytes, qiov, flags);
+    return bdrv_co_pwritev(bs->file, offset, bytes, qiov, flags);
 }
 
 static int coroutine_fn cbw_co_flush(BlockDriverState *bs)
 {
-    if (!bs->backing) {
+    if (!bs->file) {
         return 0;
     }
 
-    return bdrv_co_flush(bs->backing->bs);
+    return bdrv_co_flush(bs->file->bs);
 }
 
 static void cbw_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);
+            bs->file->bs->filename);
 }
 
 static void cbw_child_perm(BlockDriverState *bs, BdrvChild *c,
@@ -186,6 +179,7 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
     top = bdrv_new_open_driver(&bdrv_cbw_filter, filter_node_name,
                                BDRV_O_RDWR, errp);
     if (!top) {
+        error_prepend(errp, "Cannot open driver: ");
         return NULL;
     }
 
@@ -201,21 +195,32 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
     state->target = bdrv_attach_child(top, target, "target", &child_of_bds,
                                       BDRV_CHILD_DATA, errp);
     if (!state->target) {
+        error_prepend(errp, "Cannot attach target child: ");
+        bdrv_unref(top);
+        return NULL;
+    }
+
+    bdrv_ref(source);
+    top->file = bdrv_attach_child(top, source, "file", &child_of_bds,
+                                  BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY,
+                                  errp);
+    if (!top->file) {
+        error_prepend(errp, "Cannot attach file child: ");
         bdrv_unref(top);
         return NULL;
     }
 
     bdrv_drained_begin(source);
 
-    ret = bdrv_append(top, source, errp);
+    ret = bdrv_replace_node(source, top, errp);
     if (ret < 0) {
         error_prepend(errp, "Cannot append copy-before-write filter: ");
         goto fail;
     }
     appended = true;
 
-    state->bcs = block_copy_state_new(top->backing, state->target,
-                                      false, compress, errp);
+    state->bcs = block_copy_state_new(top->file, state->target, false, compress,
+                                      errp);
     if (!state->bcs) {
         error_prepend(errp, "Cannot create block-copy-state: ");
         goto fail;
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 13/33] block/copy-before-write: bdrv_cbw_append(): replace child at last
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (11 preceding siblings ...)
  2021-08-04  9:37 ` [PATCH v7 12/33] block/copy-before-write: use file child instead of backing Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:37 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:37 ` [PATCH v7 14/33] block/copy-before-write: introduce cbw_init() Vladimir Sementsov-Ogievskiy
                   ` (19 subsequent siblings)
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:37 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

Refactor the function to replace child at last. Thus we don't need to
revert it and code is simplified.

block-copy state initialization being done before replacing the child
doesn't need any drained section.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 block/copy-before-write.c | 33 +++++++++++----------------------
 1 file changed, 11 insertions(+), 22 deletions(-)

diff --git a/block/copy-before-write.c b/block/copy-before-write.c
index 7a6c15f141..adbbc64aa9 100644
--- a/block/copy-before-write.c
+++ b/block/copy-before-write.c
@@ -172,7 +172,6 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
     int ret;
     BDRVCopyBeforeWriteState *state;
     BlockDriverState *top;
-    bool appended = false;
 
     assert(source->total_sectors == target->total_sectors);
 
@@ -196,8 +195,7 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
                                       BDRV_CHILD_DATA, errp);
     if (!state->target) {
         error_prepend(errp, "Cannot attach target child: ");
-        bdrv_unref(top);
-        return NULL;
+        goto fail;
     }
 
     bdrv_ref(source);
@@ -206,18 +204,8 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
                                   errp);
     if (!top->file) {
         error_prepend(errp, "Cannot attach file child: ");
-        bdrv_unref(top);
-        return NULL;
-    }
-
-    bdrv_drained_begin(source);
-
-    ret = bdrv_replace_node(source, top, errp);
-    if (ret < 0) {
-        error_prepend(errp, "Cannot append copy-before-write filter: ");
         goto fail;
     }
-    appended = true;
 
     state->bcs = block_copy_state_new(top->file, state->target, false, compress,
                                       errp);
@@ -225,21 +213,22 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
         error_prepend(errp, "Cannot create block-copy-state: ");
         goto fail;
     }
-    *bcs = state->bcs;
 
+    bdrv_drained_begin(source);
+    ret = bdrv_replace_node(source, top, errp);
     bdrv_drained_end(source);
+    if (ret < 0) {
+        error_prepend(errp, "Cannot append copy-before-write filter: ");
+        goto fail;
+    }
+
+    *bcs = state->bcs;
 
     return top;
 
 fail:
-    if (appended) {
-        bdrv_cbw_drop(top);
-    } else {
-        bdrv_unref(top);
-    }
-
-    bdrv_drained_end(source);
-
+    block_copy_state_free(state->bcs);
+    bdrv_unref(top);
     return NULL;
 }
 
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 14/33] block/copy-before-write: introduce cbw_init()
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (12 preceding siblings ...)
  2021-08-04  9:37 ` [PATCH v7 13/33] block/copy-before-write: bdrv_cbw_append(): replace child at last Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:37 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:37 ` [PATCH v7 15/33] block/copy-before-write: cbw_init(): rename variables Vladimir Sementsov-Ogievskiy
                   ` (18 subsequent siblings)
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:37 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

Move part of bdrv_cbw_append() to new function cbw_open(). It's an
intermediate step for adding normal .bdrv_open() handler to the
filter. With this commit no logic is changed, but we have a function
which will be turned into .bdrv_open() handler in future commit.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 block/copy-before-write.c | 69 +++++++++++++++++++++++----------------
 1 file changed, 41 insertions(+), 28 deletions(-)

diff --git a/block/copy-before-write.c b/block/copy-before-write.c
index adbbc64aa9..a4fee645fd 100644
--- a/block/copy-before-write.c
+++ b/block/copy-before-write.c
@@ -144,6 +144,45 @@ static void cbw_child_perm(BlockDriverState *bs, BdrvChild *c,
     }
 }
 
+static int cbw_init(BlockDriverState *top, BlockDriverState *source,
+                    BlockDriverState *target, bool compress, Error **errp)
+{
+    BDRVCopyBeforeWriteState *state = top->opaque;
+
+    top->total_sectors = source->total_sectors;
+    top->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED |
+            (BDRV_REQ_FUA & source->supported_write_flags);
+    top->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED |
+            ((BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK) &
+             source->supported_zero_flags);
+
+    bdrv_ref(target);
+    state->target = bdrv_attach_child(top, target, "target", &child_of_bds,
+                                      BDRV_CHILD_DATA, errp);
+    if (!state->target) {
+        error_prepend(errp, "Cannot attach target child: ");
+        return -EINVAL;
+    }
+
+    bdrv_ref(source);
+    top->file = bdrv_attach_child(top, source, "file", &child_of_bds,
+                                  BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY,
+                                  errp);
+    if (!top->file) {
+        error_prepend(errp, "Cannot attach file child: ");
+        return -EINVAL;
+    }
+
+    state->bcs = block_copy_state_new(top->file, state->target, false, compress,
+                                      errp);
+    if (!state->bcs) {
+        error_prepend(errp, "Cannot create block-copy-state: ");
+        return -EINVAL;
+    }
+
+    return 0;
+}
+
 BlockDriver bdrv_cbw_filter = {
     .format_name = "copy-before-write",
     .instance_size = sizeof(BDRVCopyBeforeWriteState),
@@ -181,36 +220,10 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
         error_prepend(errp, "Cannot open driver: ");
         return NULL;
     }
-
     state = top->opaque;
-    top->total_sectors = source->total_sectors;
-    top->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED |
-            (BDRV_REQ_FUA & source->supported_write_flags);
-    top->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED |
-            ((BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK) &
-             source->supported_zero_flags);
-
-    bdrv_ref(target);
-    state->target = bdrv_attach_child(top, target, "target", &child_of_bds,
-                                      BDRV_CHILD_DATA, errp);
-    if (!state->target) {
-        error_prepend(errp, "Cannot attach target child: ");
-        goto fail;
-    }
 
-    bdrv_ref(source);
-    top->file = bdrv_attach_child(top, source, "file", &child_of_bds,
-                                  BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY,
-                                  errp);
-    if (!top->file) {
-        error_prepend(errp, "Cannot attach file child: ");
-        goto fail;
-    }
-
-    state->bcs = block_copy_state_new(top->file, state->target, false, compress,
-                                      errp);
-    if (!state->bcs) {
-        error_prepend(errp, "Cannot create block-copy-state: ");
+    ret = cbw_init(top, source, target, compress, errp);
+    if (ret < 0) {
         goto fail;
     }
 
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 15/33] block/copy-before-write: cbw_init(): rename variables
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (13 preceding siblings ...)
  2021-08-04  9:37 ` [PATCH v7 14/33] block/copy-before-write: introduce cbw_init() Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:37 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:37 ` [PATCH v7 16/33] block/copy-before-write: cbw_init(): use file child after attaching Vladimir Sementsov-Ogievskiy
                   ` (17 subsequent siblings)
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:37 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

One more step closer to real .bdrv_open() handler: use more usual names
for bs being initialized and its state.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 block/copy-before-write.c | 29 ++++++++++++++---------------
 1 file changed, 14 insertions(+), 15 deletions(-)

diff --git a/block/copy-before-write.c b/block/copy-before-write.c
index a4fee645fd..d7f1833efa 100644
--- a/block/copy-before-write.c
+++ b/block/copy-before-write.c
@@ -144,38 +144,37 @@ static void cbw_child_perm(BlockDriverState *bs, BdrvChild *c,
     }
 }
 
-static int cbw_init(BlockDriverState *top, BlockDriverState *source,
+static int cbw_init(BlockDriverState *bs, BlockDriverState *source,
                     BlockDriverState *target, bool compress, Error **errp)
 {
-    BDRVCopyBeforeWriteState *state = top->opaque;
+    BDRVCopyBeforeWriteState *s = bs->opaque;
 
-    top->total_sectors = source->total_sectors;
-    top->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED |
+    bs->total_sectors = source->total_sectors;
+    bs->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED |
             (BDRV_REQ_FUA & source->supported_write_flags);
-    top->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED |
+    bs->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED |
             ((BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK) &
              source->supported_zero_flags);
 
     bdrv_ref(target);
-    state->target = bdrv_attach_child(top, target, "target", &child_of_bds,
-                                      BDRV_CHILD_DATA, errp);
-    if (!state->target) {
+    s->target = bdrv_attach_child(bs, target, "target", &child_of_bds,
+                                  BDRV_CHILD_DATA, errp);
+    if (!s->target) {
         error_prepend(errp, "Cannot attach target child: ");
         return -EINVAL;
     }
 
     bdrv_ref(source);
-    top->file = bdrv_attach_child(top, source, "file", &child_of_bds,
-                                  BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY,
-                                  errp);
-    if (!top->file) {
+    bs->file = bdrv_attach_child(bs, source, "file", &child_of_bds,
+                                 BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY,
+                                 errp);
+    if (!bs->file) {
         error_prepend(errp, "Cannot attach file child: ");
         return -EINVAL;
     }
 
-    state->bcs = block_copy_state_new(top->file, state->target, false, compress,
-                                      errp);
-    if (!state->bcs) {
+    s->bcs = block_copy_state_new(bs->file, s->target, false, compress, errp);
+    if (!s->bcs) {
         error_prepend(errp, "Cannot create block-copy-state: ");
         return -EINVAL;
     }
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 16/33] block/copy-before-write: cbw_init(): use file child after attaching
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (14 preceding siblings ...)
  2021-08-04  9:37 ` [PATCH v7 15/33] block/copy-before-write: cbw_init(): rename variables Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:37 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:37 ` [PATCH v7 17/33] block/copy-before-write: bdrv_cbw_append(): drop unused compress arg Vladimir Sementsov-Ogievskiy
                   ` (16 subsequent siblings)
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:37 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

In the next commit we'll get rid of source argument of cbw_init().
Prepare to it now, to make next commit simpler: move the code block
that uses source below attaching the child and use bs->file->bs instead
of source variable.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 block/copy-before-write.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/block/copy-before-write.c b/block/copy-before-write.c
index d7f1833efa..4858dcf8ff 100644
--- a/block/copy-before-write.c
+++ b/block/copy-before-write.c
@@ -149,13 +149,6 @@ static int cbw_init(BlockDriverState *bs, BlockDriverState *source,
 {
     BDRVCopyBeforeWriteState *s = bs->opaque;
 
-    bs->total_sectors = source->total_sectors;
-    bs->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED |
-            (BDRV_REQ_FUA & source->supported_write_flags);
-    bs->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED |
-            ((BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK) &
-             source->supported_zero_flags);
-
     bdrv_ref(target);
     s->target = bdrv_attach_child(bs, target, "target", &child_of_bds,
                                   BDRV_CHILD_DATA, errp);
@@ -173,6 +166,13 @@ static int cbw_init(BlockDriverState *bs, BlockDriverState *source,
         return -EINVAL;
     }
 
+    bs->total_sectors = bs->file->bs->total_sectors;
+    bs->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED |
+            (BDRV_REQ_FUA & bs->file->bs->supported_write_flags);
+    bs->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED |
+            ((BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK) &
+             bs->file->bs->supported_zero_flags);
+
     s->bcs = block_copy_state_new(bs->file, s->target, false, compress, errp);
     if (!s->bcs) {
         error_prepend(errp, "Cannot create block-copy-state: ");
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 17/33] block/copy-before-write: bdrv_cbw_append(): drop unused compress arg
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (15 preceding siblings ...)
  2021-08-04  9:37 ` [PATCH v7 16/33] block/copy-before-write: cbw_init(): use file child after attaching Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:37 ` Vladimir Sementsov-Ogievskiy
  2021-08-10 15:17   ` Hanna Reitz
  2021-08-04  9:37 ` [PATCH v7 18/33] block/copy-before-write: cbw_init(): use options Vladimir Sementsov-Ogievskiy
                   ` (15 subsequent siblings)
  32 siblings, 1 reply; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:37 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 block/copy-before-write.h | 1 -
 block/backup.c            | 2 +-
 block/copy-before-write.c | 7 +++----
 3 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/block/copy-before-write.h b/block/copy-before-write.h
index b386fd8f01..51847e711a 100644
--- a/block/copy-before-write.h
+++ b/block/copy-before-write.h
@@ -32,7 +32,6 @@
 BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
                                   BlockDriverState *target,
                                   const char *filter_node_name,
-                                  bool compress,
                                   BlockCopyState **bcs,
                                   Error **errp);
 void bdrv_cbw_drop(BlockDriverState *bs);
diff --git a/block/backup.c b/block/backup.c
index 83516297cb..4869f1e5da 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -452,7 +452,7 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
         goto error;
     }
 
-    cbw = bdrv_cbw_append(bs, target, filter_node_name, false, &bcs, errp);
+    cbw = bdrv_cbw_append(bs, target, filter_node_name, &bcs, errp);
     if (!cbw) {
         goto error;
     }
diff --git a/block/copy-before-write.c b/block/copy-before-write.c
index 4858dcf8ff..1e7180760a 100644
--- a/block/copy-before-write.c
+++ b/block/copy-before-write.c
@@ -145,7 +145,7 @@ static void cbw_child_perm(BlockDriverState *bs, BdrvChild *c,
 }
 
 static int cbw_init(BlockDriverState *bs, BlockDriverState *source,
-                    BlockDriverState *target, bool compress, Error **errp)
+                    BlockDriverState *target, Error **errp)
 {
     BDRVCopyBeforeWriteState *s = bs->opaque;
 
@@ -173,7 +173,7 @@ static int cbw_init(BlockDriverState *bs, BlockDriverState *source,
             ((BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK) &
              bs->file->bs->supported_zero_flags);
 
-    s->bcs = block_copy_state_new(bs->file, s->target, false, compress, errp);
+    s->bcs = block_copy_state_new(bs->file, s->target, false, false, errp);
     if (!s->bcs) {
         error_prepend(errp, "Cannot create block-copy-state: ");
         return -EINVAL;
@@ -202,7 +202,6 @@ BlockDriver bdrv_cbw_filter = {
 BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
                                   BlockDriverState *target,
                                   const char *filter_node_name,
-                                  bool compress,
                                   BlockCopyState **bcs,
                                   Error **errp)
 {
@@ -221,7 +220,7 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
     }
     state = top->opaque;
 
-    ret = cbw_init(top, source, target, compress, errp);
+    ret = cbw_init(top, source, target, errp);
     if (ret < 0) {
         goto fail;
     }
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 18/33] block/copy-before-write: cbw_init(): use options
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (16 preceding siblings ...)
  2021-08-04  9:37 ` [PATCH v7 17/33] block/copy-before-write: bdrv_cbw_append(): drop unused compress arg Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:37 ` Vladimir Sementsov-Ogievskiy
  2021-08-10 15:18   ` Hanna Reitz
  2021-08-04  9:37 ` [PATCH v7 19/33] block/copy-before-write: initialize block-copy bitmap Vladimir Sementsov-Ogievskiy
                   ` (14 subsequent siblings)
  32 siblings, 1 reply; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:37 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

One more step closer to .bdrv_open(): use options instead of plain
arguments. Move to bdrv_open_child() calls, native for drive open
handlers.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 block/copy-before-write.c | 29 +++++++++++++++--------------
 1 file changed, 15 insertions(+), 14 deletions(-)

diff --git a/block/copy-before-write.c b/block/copy-before-write.c
index 1e7180760a..1cefcade78 100644
--- a/block/copy-before-write.c
+++ b/block/copy-before-write.c
@@ -144,25 +144,20 @@ static void cbw_child_perm(BlockDriverState *bs, BdrvChild *c,
     }
 }
 
-static int cbw_init(BlockDriverState *bs, BlockDriverState *source,
-                    BlockDriverState *target, Error **errp)
+static int cbw_init(BlockDriverState *bs, QDict *options, Error **errp)
 {
     BDRVCopyBeforeWriteState *s = bs->opaque;
 
-    bdrv_ref(target);
-    s->target = bdrv_attach_child(bs, target, "target", &child_of_bds,
-                                  BDRV_CHILD_DATA, errp);
-    if (!s->target) {
-        error_prepend(errp, "Cannot attach target child: ");
+    bs->file = bdrv_open_child(NULL, options, "file", bs, &child_of_bds,
+                               BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY,
+                               false, errp);
+    if (!bs->file) {
         return -EINVAL;
     }
 
-    bdrv_ref(source);
-    bs->file = bdrv_attach_child(bs, source, "file", &child_of_bds,
-                                 BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY,
-                                 errp);
-    if (!bs->file) {
-        error_prepend(errp, "Cannot attach file child: ");
+    s->target = bdrv_open_child(NULL, options, "target", bs, &child_of_bds,
+                                BDRV_CHILD_DATA, false, errp);
+    if (!s->target) {
         return -EINVAL;
     }
 
@@ -209,6 +204,7 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
     int ret;
     BDRVCopyBeforeWriteState *state;
     BlockDriverState *top;
+    QDict *opts;
 
     assert(source->total_sectors == target->total_sectors);
 
@@ -220,7 +216,12 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
     }
     state = top->opaque;
 
-    ret = cbw_init(top, source, target, errp);
+    opts = qdict_new();
+    qdict_put_str(opts, "file", bdrv_get_node_name(source));
+    qdict_put_str(opts, "target", bdrv_get_node_name(target));
+
+    ret = cbw_init(top, opts, errp);
+    qobject_unref(opts);
     if (ret < 0) {
         goto fail;
     }
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 19/33] block/copy-before-write: initialize block-copy bitmap
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (17 preceding siblings ...)
  2021-08-04  9:37 ` [PATCH v7 18/33] block/copy-before-write: cbw_init(): use options Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:37 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:38 ` [PATCH v7 20/33] block/block-copy: make setting progress optional Vladimir Sementsov-Ogievskiy
                   ` (13 subsequent siblings)
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:37 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

We are going to publish copy-before-write filter to be used in separate
of backup. Future step would support bitmap for the filter. But let's
start from full set bitmap.

We have to modify backup, as bitmap is first initialized by
copy-before-write filter, and then backup modifies it.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 block/backup.c            | 16 +++++++---------
 block/copy-before-write.c |  4 ++++
 2 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/block/backup.c b/block/backup.c
index 4869f1e5da..687d2882bc 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -233,18 +233,16 @@ static void backup_init_bcs_bitmap(BackupBlockJob *job)
     BdrvDirtyBitmap *bcs_bitmap = block_copy_dirty_bitmap(job->bcs);
 
     if (job->sync_mode == MIRROR_SYNC_MODE_BITMAP) {
+        bdrv_clear_dirty_bitmap(bcs_bitmap, NULL);
         ret = bdrv_dirty_bitmap_merge_internal(bcs_bitmap, job->sync_bitmap,
                                                NULL, true);
         assert(ret);
-    } else {
-        if (job->sync_mode == MIRROR_SYNC_MODE_TOP) {
-            /*
-             * We can't hog the coroutine to initialize this thoroughly.
-             * Set a flag and resume work when we are able to yield safely.
-             */
-            block_copy_set_skip_unallocated(job->bcs, true);
-        }
-        bdrv_set_dirty_bitmap(bcs_bitmap, 0, job->len);
+    } else if (job->sync_mode == MIRROR_SYNC_MODE_TOP) {
+        /*
+         * We can't hog the coroutine to initialize this thoroughly.
+         * Set a flag and resume work when we are able to yield safely.
+         */
+        block_copy_set_skip_unallocated(job->bcs, true);
     }
 
     estimate = bdrv_get_dirty_count(bcs_bitmap);
diff --git a/block/copy-before-write.c b/block/copy-before-write.c
index 1cefcade78..2efe098aae 100644
--- a/block/copy-before-write.c
+++ b/block/copy-before-write.c
@@ -147,6 +147,7 @@ static void cbw_child_perm(BlockDriverState *bs, BdrvChild *c,
 static int cbw_init(BlockDriverState *bs, QDict *options, Error **errp)
 {
     BDRVCopyBeforeWriteState *s = bs->opaque;
+    BdrvDirtyBitmap *copy_bitmap;
 
     bs->file = bdrv_open_child(NULL, options, "file", bs, &child_of_bds,
                                BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY,
@@ -174,6 +175,9 @@ static int cbw_init(BlockDriverState *bs, QDict *options, Error **errp)
         return -EINVAL;
     }
 
+    copy_bitmap = block_copy_dirty_bitmap(s->bcs);
+    bdrv_set_dirty_bitmap(copy_bitmap, 0, bdrv_dirty_bitmap_size(copy_bitmap));
+
     return 0;
 }
 
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 20/33] block/block-copy: make setting progress optional
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (18 preceding siblings ...)
  2021-08-04  9:37 ` [PATCH v7 19/33] block/copy-before-write: initialize block-copy bitmap Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:38 ` Vladimir Sementsov-Ogievskiy
  2021-08-10 15:23   ` Hanna Reitz
  2021-08-04  9:38 ` [PATCH v7 21/33] block/copy-before-write: make public block driver Vladimir Sementsov-Ogievskiy
                   ` (12 subsequent siblings)
  32 siblings, 1 reply; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:38 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

Now block-copy will crash if user don't set progress meter by
block_copy_set_progress_meter(). copy-before-write filter will be used
in separate of backup job, and it doesn't want any progress meter (for
now). So, allow not setting it.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 block/block-copy.c | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/block/block-copy.c b/block/block-copy.c
index 78ee255fd0..90664ee0ab 100644
--- a/block/block-copy.c
+++ b/block/block-copy.c
@@ -291,9 +291,11 @@ static void coroutine_fn block_copy_task_end(BlockCopyTask *task, int ret)
         bdrv_set_dirty_bitmap(task->s->copy_bitmap, task->offset, task->bytes);
     }
     QLIST_REMOVE(task, list);
-    progress_set_remaining(task->s->progress,
-                           bdrv_get_dirty_count(task->s->copy_bitmap) +
-                           task->s->in_flight_bytes);
+    if (task->s->progress) {
+        progress_set_remaining(task->s->progress,
+                               bdrv_get_dirty_count(task->s->copy_bitmap) +
+                               task->s->in_flight_bytes);
+    }
     qemu_co_queue_restart_all(&task->wait_queue);
 }
 
@@ -592,7 +594,7 @@ static coroutine_fn int block_copy_task_entry(AioTask *task)
                 t->call_state->ret = ret;
                 t->call_state->error_is_read = error_is_read;
             }
-        } else {
+        } else if (s->progress) {
             progress_work_done(s->progress, t->bytes);
         }
     }
@@ -698,9 +700,11 @@ int64_t block_copy_reset_unallocated(BlockCopyState *s,
     if (!ret) {
         qemu_co_mutex_lock(&s->lock);
         bdrv_reset_dirty_bitmap(s->copy_bitmap, offset, bytes);
-        progress_set_remaining(s->progress,
-                               bdrv_get_dirty_count(s->copy_bitmap) +
-                               s->in_flight_bytes);
+        if (s->progress) {
+            progress_set_remaining(s->progress,
+                                   bdrv_get_dirty_count(s->copy_bitmap) +
+                                   s->in_flight_bytes);
+        }
         qemu_co_mutex_unlock(&s->lock);
     }
 
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 21/33] block/copy-before-write: make public block driver
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (19 preceding siblings ...)
  2021-08-04  9:38 ` [PATCH v7 20/33] block/block-copy: make setting progress optional Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:38 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:38 ` [PATCH v7 22/33] qapi: publish copy-before-write filter Vladimir Sementsov-Ogievskiy
                   ` (11 subsequent siblings)
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:38 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

Finally, copy-before-write gets own .bdrv_open and .bdrv_close
handlers, block_init() call and becomes available through bdrv_open().

To achieve this:

 - cbw_init gets unused flags argument and becomes cbw_open
 - block_copy_state_free() call moved to new cbw_close()
 - in bdrv_cbw_append:
   - options are completed with driver and node-name, and we can simply
     use bdrv_insert_node() to do both open and drained replacing
 - in bdrv_cbw_drop:
   - cbw_close() is now responsible for freeing s->bcs, so don't do it
     here

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 block/copy-before-write.c | 60 ++++++++++++++++++---------------------
 1 file changed, 28 insertions(+), 32 deletions(-)

diff --git a/block/copy-before-write.c b/block/copy-before-write.c
index 2efe098aae..2cd68b480a 100644
--- a/block/copy-before-write.c
+++ b/block/copy-before-write.c
@@ -144,7 +144,8 @@ static void cbw_child_perm(BlockDriverState *bs, BdrvChild *c,
     }
 }
 
-static int cbw_init(BlockDriverState *bs, QDict *options, Error **errp)
+static int cbw_open(BlockDriverState *bs, QDict *options, int flags,
+                    Error **errp)
 {
     BDRVCopyBeforeWriteState *s = bs->opaque;
     BdrvDirtyBitmap *copy_bitmap;
@@ -181,10 +182,21 @@ static int cbw_init(BlockDriverState *bs, QDict *options, Error **errp)
     return 0;
 }
 
+static void cbw_close(BlockDriverState *bs)
+{
+    BDRVCopyBeforeWriteState *s = bs->opaque;
+
+    block_copy_state_free(s->bcs);
+    s->bcs = NULL;
+}
+
 BlockDriver bdrv_cbw_filter = {
     .format_name = "copy-before-write",
     .instance_size = sizeof(BDRVCopyBeforeWriteState),
 
+    .bdrv_open                  = cbw_open,
+    .bdrv_close                 = cbw_close,
+
     .bdrv_co_preadv             = cbw_co_preadv,
     .bdrv_co_pwritev            = cbw_co_pwritev,
     .bdrv_co_pwrite_zeroes      = cbw_co_pwrite_zeroes,
@@ -205,56 +217,40 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
                                   Error **errp)
 {
     ERRP_GUARD();
-    int ret;
     BDRVCopyBeforeWriteState *state;
     BlockDriverState *top;
     QDict *opts;
 
     assert(source->total_sectors == target->total_sectors);
 
-    top = bdrv_new_open_driver(&bdrv_cbw_filter, filter_node_name,
-                               BDRV_O_RDWR, errp);
-    if (!top) {
-        error_prepend(errp, "Cannot open driver: ");
-        return NULL;
-    }
-    state = top->opaque;
-
     opts = qdict_new();
+    qdict_put_str(opts, "driver", "copy-before-write");
+    if (filter_node_name) {
+        qdict_put_str(opts, "node-name", filter_node_name);
+    }
     qdict_put_str(opts, "file", bdrv_get_node_name(source));
     qdict_put_str(opts, "target", bdrv_get_node_name(target));
 
-    ret = cbw_init(top, opts, errp);
-    qobject_unref(opts);
-    if (ret < 0) {
-        goto fail;
-    }
-
-    bdrv_drained_begin(source);
-    ret = bdrv_replace_node(source, top, errp);
-    bdrv_drained_end(source);
-    if (ret < 0) {
-        error_prepend(errp, "Cannot append copy-before-write filter: ");
-        goto fail;
+    top = bdrv_insert_node(source, opts, BDRV_O_RDWR, errp);
+    if (!top) {
+        return NULL;
     }
 
+    state = top->opaque;
     *bcs = state->bcs;
 
     return top;
-
-fail:
-    block_copy_state_free(state->bcs);
-    bdrv_unref(top);
-    return NULL;
 }
 
 void bdrv_cbw_drop(BlockDriverState *bs)
 {
-    BDRVCopyBeforeWriteState *s = bs->opaque;
-
     bdrv_drop_filter(bs, &error_abort);
-
-    block_copy_state_free(s->bcs);
-
     bdrv_unref(bs);
 }
+
+static void cbw_init(void)
+{
+    bdrv_register(&bdrv_cbw_filter);
+}
+
+block_init(cbw_init);
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 22/33] qapi: publish copy-before-write filter
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (20 preceding siblings ...)
  2021-08-04  9:38 ` [PATCH v7 21/33] block/copy-before-write: make public block driver Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:38 ` Vladimir Sementsov-Ogievskiy
  2021-08-04 13:18   ` Markus Armbruster
  2021-08-04  9:38 ` [PATCH v7 23/33] python/qemu/machine.py: refactor _qemu_args() Vladimir Sementsov-Ogievskiy
                   ` (10 subsequent siblings)
  32 siblings, 1 reply; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:38 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 qapi/block-core.json | 25 +++++++++++++++++++++++--
 1 file changed, 23 insertions(+), 2 deletions(-)

diff --git a/qapi/block-core.json b/qapi/block-core.json
index 675d8265eb..59d3e5e42d 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -2825,13 +2825,14 @@
 # @blklogwrites: Since 3.0
 # @blkreplay: Since 4.2
 # @compress: Since 5.0
+# @copy-before-write: Since 6.1
 #
 # Since: 2.9
 ##
 { 'enum': 'BlockdevDriver',
   'data': [ 'blkdebug', 'blklogwrites', 'blkreplay', 'blkverify', 'bochs',
-            'cloop', 'compress', 'copy-on-read', 'dmg', 'file', 'ftp', 'ftps',
-            'gluster',
+            'cloop', 'compress', 'copy-before-write', 'copy-on-read', 'dmg',
+            'file', 'ftp', 'ftps', 'gluster',
             {'name': 'host_cdrom', 'if': 'defined(HAVE_HOST_BLOCK_DEVICE)' },
             {'name': 'host_device', 'if': 'defined(HAVE_HOST_BLOCK_DEVICE)' },
             'http', 'https', 'iscsi',
@@ -4049,6 +4050,25 @@
   'base': 'BlockdevOptionsGenericFormat',
   'data': { '*bottom': 'str' } }
 
+##
+# @BlockdevOptionsCbw:
+#
+# Driver specific block device options for the copy-before-write driver,
+# which does so called copy-before-write operations: when data is
+# written to the filter, the filter firstly reads corresponding blocks
+# from its file child and copies them to @target child. After successful
+# copying the write request is propagated to file child. If copying
+# failed, the original write request is failed too and no data is written
+# to file child.
+#
+# @target: The target for copy-before-write operations.
+#
+# Since: 6.1
+##
+{ 'struct': 'BlockdevOptionsCbw',
+  'base': 'BlockdevOptionsGenericFormat',
+  'data': { 'target': 'BlockdevRef' } }
+
 ##
 # @BlockdevOptions:
 #
@@ -4101,6 +4121,7 @@
       'bochs':      'BlockdevOptionsGenericFormat',
       'cloop':      'BlockdevOptionsGenericFormat',
       'compress':   'BlockdevOptionsGenericFormat',
+      'copy-before-write':'BlockdevOptionsCbw',
       'copy-on-read':'BlockdevOptionsCor',
       'dmg':        'BlockdevOptionsGenericFormat',
       'file':       'BlockdevOptionsFile',
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 23/33] python/qemu/machine.py: refactor _qemu_args()
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (21 preceding siblings ...)
  2021-08-04  9:38 ` [PATCH v7 22/33] qapi: publish copy-before-write filter Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:38 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:38 ` [PATCH v7 24/33] python/qemu/machine: QEMUMachine: improve qmp() method Vladimir Sementsov-Ogievskiy
                   ` (9 subsequent siblings)
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:38 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

 - use shorter construction
 - don't create new dict if not needed
 - drop extra unpacking key-val arguments
 - drop extra default values

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
---
 python/qemu/machine/machine.py | 18 ++++++++----------
 1 file changed, 8 insertions(+), 10 deletions(-)

diff --git a/python/qemu/machine/machine.py b/python/qemu/machine/machine.py
index 971ed7e8c6..5eab31aeec 100644
--- a/python/qemu/machine/machine.py
+++ b/python/qemu/machine/machine.py
@@ -564,14 +564,12 @@ def _qmp(self) -> QEMUMonitorProtocol:
         return self._qmp_connection
 
     @classmethod
-    def _qmp_args(cls, _conv_keys: bool = True, **args: Any) -> Dict[str, Any]:
-        qmp_args = dict()
-        for key, value in args.items():
-            if _conv_keys:
-                qmp_args[key.replace('_', '-')] = value
-            else:
-                qmp_args[key] = value
-        return qmp_args
+    def _qmp_args(cls, conv_keys: bool,
+                  args: Dict[str, Any]) -> Dict[str, object]:
+        if conv_keys:
+            return {k.replace('_', '-'): v for k, v in args.items()}
+
+        return args
 
     def qmp(self, cmd: str,
             conv_keys: bool = True,
@@ -579,7 +577,7 @@ def qmp(self, cmd: str,
         """
         Invoke a QMP command and return the response dict
         """
-        qmp_args = self._qmp_args(conv_keys, **args)
+        qmp_args = self._qmp_args(conv_keys, args)
         return self._qmp.cmd(cmd, args=qmp_args)
 
     def command(self, cmd: str,
@@ -590,7 +588,7 @@ def command(self, cmd: str,
         On success return the response dict.
         On failure raise an exception.
         """
-        qmp_args = self._qmp_args(conv_keys, **args)
+        qmp_args = self._qmp_args(conv_keys, args)
         return self._qmp.command(cmd, **qmp_args)
 
     def get_qmp_event(self, wait: bool = False) -> Optional[QMPMessage]:
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 24/33] python/qemu/machine: QEMUMachine: improve qmp() method
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (22 preceding siblings ...)
  2021-08-04  9:38 ` [PATCH v7 23/33] python/qemu/machine.py: refactor _qemu_args() Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:38 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:38 ` [PATCH v7 25/33] iotests.py: VM: add own __enter__ method Vladimir Sementsov-Ogievskiy
                   ` (8 subsequent siblings)
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:38 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

We often call qmp() with unpacking dict, like qmp('foo', **{...}).
mypy don't really like it, it thinks that passed unpacked dict is a
positional argument and complains that it type should be bool (because
second argument of qmp() is conv_keys: bool).

Allow passing dict directly, simplifying interface, and giving a way to
satisfy mypy.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
---
 python/qemu/machine/machine.py | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/python/qemu/machine/machine.py b/python/qemu/machine/machine.py
index 5eab31aeec..ce1e130c13 100644
--- a/python/qemu/machine/machine.py
+++ b/python/qemu/machine/machine.py
@@ -572,11 +572,21 @@ def _qmp_args(cls, conv_keys: bool,
         return args
 
     def qmp(self, cmd: str,
-            conv_keys: bool = True,
+            args_dict: Optional[Dict[str, object]] = None,
+            conv_keys: Optional[bool] = None,
             **args: Any) -> QMPMessage:
         """
         Invoke a QMP command and return the response dict
         """
+        if args_dict is not None:
+            assert not args
+            assert conv_keys is None
+            args = args_dict
+            conv_keys = False
+
+        if conv_keys is None:
+            conv_keys = True
+
         qmp_args = self._qmp_args(conv_keys, args)
         return self._qmp.cmd(cmd, args=qmp_args)
 
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 25/33] iotests.py: VM: add own __enter__ method
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (23 preceding siblings ...)
  2021-08-04  9:38 ` [PATCH v7 24/33] python/qemu/machine: QEMUMachine: improve qmp() method Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:38 ` Vladimir Sementsov-Ogievskiy
  2021-08-04 16:27   ` John Snow
  2021-08-04  9:38 ` [PATCH v7 26/33] iotests/222: fix pylint and mypy complains Vladimir Sementsov-Ogievskiy
                   ` (7 subsequent siblings)
  32 siblings, 1 reply; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:38 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

In superclass __enter__ method is defined with return value type hint
'QEMUMachine'. So, mypy thinks that return value of VM.__enter__ is
QEMUMachine. Let's redefine __enter__ in VM class, to give it correct
type hint.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 tests/qemu-iotests/iotests.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
index 89663dac06..025e288ddd 100644
--- a/tests/qemu-iotests/iotests.py
+++ b/tests/qemu-iotests/iotests.py
@@ -568,6 +568,10 @@ def remote_filename(path):
 class VM(qtest.QEMUQtestMachine):
     '''A QEMU VM'''
 
+    # Redefine __enter__ with proper type hint
+    def __enter__(self) -> 'VM':
+        return self
+
     def __init__(self, path_suffix=''):
         name = "qemu%s-%d" % (path_suffix, os.getpid())
         super().__init__(qemu_prog, qemu_opts, name=name,
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 26/33] iotests/222: fix pylint and mypy complains
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (24 preceding siblings ...)
  2021-08-04  9:38 ` [PATCH v7 25/33] iotests.py: VM: add own __enter__ method Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:38 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:38 ` [PATCH v7 27/33] iotests/222: constantly use single quotes for strings Vladimir Sementsov-Ogievskiy
                   ` (6 subsequent siblings)
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:38 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

Here:
 - long line
 - move to new interface of vm.qmp() (direct passing dict), to avoid
   mypy false-positive, as it thinks that unpacked dict is a positional
   argument.
 - extra parenthesis
 - handle event_wait possible None value

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 tests/qemu-iotests/222 | 20 +++++++++++---------
 tests/qemu-iotests/297 |  2 +-
 2 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/tests/qemu-iotests/222 b/tests/qemu-iotests/222
index b48afe623e..5e2556f8df 100755
--- a/tests/qemu-iotests/222
+++ b/tests/qemu-iotests/222
@@ -50,7 +50,8 @@ remainder = [("0xd5", "0x108000",  "32k"), # Right-end of partial-left [1]
 
 with iotests.FilePath('base.img') as base_img_path, \
      iotests.FilePath('fleece.img') as fleece_img_path, \
-     iotests.FilePath('nbd.sock', base_dir=iotests.sock_dir) as nbd_sock_path, \
+     iotests.FilePath('nbd.sock',
+                      base_dir=iotests.sock_dir) as nbd_sock_path, \
      iotests.VM() as vm:
 
     log('--- Setting up images ---')
@@ -81,7 +82,7 @@ with iotests.FilePath('base.img') as base_img_path, \
     tgt_node = "fleeceNode"
 
     # create tgt_node backed by src_node
-    log(vm.qmp("blockdev-add", **{
+    log(vm.qmp("blockdev-add", {
         "driver": "qcow2",
         "node-name": tgt_node,
         "file": {
@@ -103,8 +104,8 @@ with iotests.FilePath('base.img') as base_img_path, \
 
     nbd_uri = 'nbd+unix:///%s?socket=%s' % (tgt_node, nbd_sock_path)
     log(vm.qmp("nbd-server-start",
-               **{"addr": { "type": "unix",
-                            "data": { "path": nbd_sock_path } } }))
+               {"addr": { "type": "unix",
+                          "data": { "path": nbd_sock_path } } }))
 
     log(vm.qmp("nbd-server-add", device=tgt_node))
 
@@ -112,7 +113,7 @@ with iotests.FilePath('base.img') as base_img_path, \
     log('--- Sanity Check ---')
     log('')
 
-    for p in (patterns + zeroes):
+    for p in patterns + zeroes:
         cmd = "read -P%s %s %s" % p
         log(cmd)
         assert qemu_io_silent('-r', '-f', 'raw', '-c', cmd, nbd_uri) == 0
@@ -130,7 +131,7 @@ with iotests.FilePath('base.img') as base_img_path, \
     log('--- Verifying Data ---')
     log('')
 
-    for p in (patterns + zeroes):
+    for p in patterns + zeroes:
         cmd = "read -P%s %s %s" % p
         log(cmd)
         assert qemu_io_silent('-r', '-f', 'raw', '-c', cmd, nbd_uri) == 0
@@ -140,8 +141,9 @@ with iotests.FilePath('base.img') as base_img_path, \
     log('')
 
     log(vm.qmp('block-job-cancel', device=src_node))
-    log(vm.event_wait('BLOCK_JOB_CANCELLED'),
-        filters=[iotests.filter_qmp_event])
+    e = vm.event_wait('BLOCK_JOB_CANCELLED')
+    assert e is not None
+    log(e, filters=[iotests.filter_qmp_event])
     log(vm.qmp('nbd-server-stop'))
     log(vm.qmp('blockdev-del', node_name=tgt_node))
     vm.shutdown()
@@ -150,7 +152,7 @@ with iotests.FilePath('base.img') as base_img_path, \
     log('--- Confirming writes ---')
     log('')
 
-    for p in (overwrite + remainder):
+    for p in overwrite + remainder:
         cmd = "read -P%s %s %s" % p
         log(cmd)
         assert qemu_io_silent(base_img_path, '-c', cmd) == 0
diff --git a/tests/qemu-iotests/297 b/tests/qemu-iotests/297
index 433b732336..345b617b34 100755
--- a/tests/qemu-iotests/297
+++ b/tests/qemu-iotests/297
@@ -31,7 +31,7 @@ SKIP_FILES = (
     '096', '118', '124', '132', '136', '139', '147', '148', '149',
     '151', '152', '155', '163', '165', '169', '194', '196', '199', '202',
     '203', '205', '206', '207', '208', '210', '211', '212', '213', '216',
-    '218', '219', '222', '224', '228', '234', '235', '236', '237', '238',
+    '218', '219', '224', '228', '234', '235', '236', '237', '238',
     '240', '242', '245', '246', '248', '255', '256', '257', '258', '260',
     '262', '264', '266', '274', '277', '280', '281', '295', '296', '298',
     '299', '302', '303', '304', '307',
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 27/33] iotests/222: constantly use single quotes for strings
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (25 preceding siblings ...)
  2021-08-04  9:38 ` [PATCH v7 26/33] iotests/222: fix pylint and mypy complains Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:38 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:38 ` [PATCH v7 28/33] iotests: move 222 to tests/image-fleecing Vladimir Sementsov-Ogievskiy
                   ` (5 subsequent siblings)
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:38 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

The file use both single and double quotes for strings. Let's be
consistent.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 tests/qemu-iotests/222 | 68 +++++++++++++++++++++---------------------
 1 file changed, 34 insertions(+), 34 deletions(-)

diff --git a/tests/qemu-iotests/222 b/tests/qemu-iotests/222
index 5e2556f8df..799369e290 100755
--- a/tests/qemu-iotests/222
+++ b/tests/qemu-iotests/222
@@ -30,23 +30,23 @@ iotests.script_initialize(
     supported_platforms=['linux'],
 )
 
-patterns = [("0x5d", "0",         "64k"),
-            ("0xd5", "1M",        "64k"),
-            ("0xdc", "32M",       "64k"),
-            ("0xcd", "0x3ff0000", "64k")]  # 64M - 64K
+patterns = [('0x5d', '0',         '64k'),
+            ('0xd5', '1M',        '64k'),
+            ('0xdc', '32M',       '64k'),
+            ('0xcd', '0x3ff0000', '64k')]  # 64M - 64K
 
-overwrite = [("0xab", "0",         "64k"), # Full overwrite
-             ("0xad", "0x00f8000", "64k"), # Partial-left (1M-32K)
-             ("0x1d", "0x2008000", "64k"), # Partial-right (32M+32K)
-             ("0xea", "0x3fe0000", "64k")] # Adjacent-left (64M - 128K)
+overwrite = [('0xab', '0',         '64k'), # Full overwrite
+             ('0xad', '0x00f8000', '64k'), # Partial-left (1M-32K)
+             ('0x1d', '0x2008000', '64k'), # Partial-right (32M+32K)
+             ('0xea', '0x3fe0000', '64k')] # Adjacent-left (64M - 128K)
 
-zeroes = [("0", "0x00f8000", "32k"), # Left-end of partial-left (1M-32K)
-          ("0", "0x2010000", "32k"), # Right-end of partial-right (32M+64K)
-          ("0", "0x3fe0000", "64k")] # overwrite[3]
+zeroes = [('0', '0x00f8000', '32k'), # Left-end of partial-left (1M-32K)
+          ('0', '0x2010000', '32k'), # Right-end of partial-right (32M+64K)
+          ('0', '0x3fe0000', '64k')] # overwrite[3]
 
-remainder = [("0xd5", "0x108000",  "32k"), # Right-end of partial-left [1]
-             ("0xdc", "32M",       "32k"), # Left-end of partial-right [2]
-             ("0xcd", "0x3ff0000", "64k")] # patterns[3]
+remainder = [('0xd5', '0x108000',  '32k'), # Right-end of partial-left [1]
+             ('0xdc', '32M',       '32k'), # Left-end of partial-right [2]
+             ('0xcd', '0x3ff0000', '64k')] # patterns[3]
 
 with iotests.FilePath('base.img') as base_img_path, \
      iotests.FilePath('fleece.img') as fleece_img_path, \
@@ -58,7 +58,7 @@ with iotests.FilePath('base.img') as base_img_path, \
     log('')
 
     assert qemu_img('create', '-f', iotests.imgfmt, base_img_path, '64M') == 0
-    assert qemu_img('create', '-f', "qcow2", fleece_img_path, '64M') == 0
+    assert qemu_img('create', '-f', 'qcow2', fleece_img_path, '64M') == 0
 
     for p in patterns:
         qemu_io('-f', iotests.imgfmt,
@@ -78,43 +78,43 @@ with iotests.FilePath('base.img') as base_img_path, \
     log('--- Setting up Fleecing Graph ---')
     log('')
 
-    src_node = "drive0"
-    tgt_node = "fleeceNode"
+    src_node = 'drive0'
+    tgt_node = 'fleeceNode'
 
     # create tgt_node backed by src_node
-    log(vm.qmp("blockdev-add", {
-        "driver": "qcow2",
-        "node-name": tgt_node,
-        "file": {
-            "driver": "file",
-            "filename": fleece_img_path,
+    log(vm.qmp('blockdev-add', {
+        'driver': 'qcow2',
+        'node-name': tgt_node,
+        'file': {
+            'driver': 'file',
+            'filename': fleece_img_path,
         },
-        "backing": src_node,
+        'backing': src_node,
     }))
 
     # Establish COW from source to fleecing node
-    log(vm.qmp("blockdev-backup",
+    log(vm.qmp('blockdev-backup',
                device=src_node,
                target=tgt_node,
-               sync="none"))
+               sync='none'))
 
     log('')
     log('--- Setting up NBD Export ---')
     log('')
 
     nbd_uri = 'nbd+unix:///%s?socket=%s' % (tgt_node, nbd_sock_path)
-    log(vm.qmp("nbd-server-start",
-               {"addr": { "type": "unix",
-                          "data": { "path": nbd_sock_path } } }))
+    log(vm.qmp('nbd-server-start',
+               {'addr': { 'type': 'unix',
+                          'data': { 'path': nbd_sock_path } } }))
 
-    log(vm.qmp("nbd-server-add", device=tgt_node))
+    log(vm.qmp('nbd-server-add', device=tgt_node))
 
     log('')
     log('--- Sanity Check ---')
     log('')
 
     for p in patterns + zeroes:
-        cmd = "read -P%s %s %s" % p
+        cmd = 'read -P%s %s %s' % p
         log(cmd)
         assert qemu_io_silent('-r', '-f', 'raw', '-c', cmd, nbd_uri) == 0
 
@@ -123,7 +123,7 @@ with iotests.FilePath('base.img') as base_img_path, \
     log('')
 
     for p in overwrite:
-        cmd = "write -P%s %s %s" % p
+        cmd = 'write -P%s %s %s' % p
         log(cmd)
         log(vm.hmp_qemu_io(src_node, cmd))
 
@@ -132,7 +132,7 @@ with iotests.FilePath('base.img') as base_img_path, \
     log('')
 
     for p in patterns + zeroes:
-        cmd = "read -P%s %s %s" % p
+        cmd = 'read -P%s %s %s' % p
         log(cmd)
         assert qemu_io_silent('-r', '-f', 'raw', '-c', cmd, nbd_uri) == 0
 
@@ -153,7 +153,7 @@ with iotests.FilePath('base.img') as base_img_path, \
     log('')
 
     for p in overwrite + remainder:
-        cmd = "read -P%s %s %s" % p
+        cmd = 'read -P%s %s %s' % p
         log(cmd)
         assert qemu_io_silent(base_img_path, '-c', cmd) == 0
 
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 28/33] iotests: move 222 to tests/image-fleecing
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (26 preceding siblings ...)
  2021-08-04  9:38 ` [PATCH v7 27/33] iotests/222: constantly use single quotes for strings Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:38 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:38 ` [PATCH v7 29/33] iotests.py: hmp_qemu_io: support qdev Vladimir Sementsov-Ogievskiy
                   ` (4 subsequent siblings)
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:38 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

Give a good name to test file.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 tests/qemu-iotests/{222 => tests/image-fleecing}         | 0
 tests/qemu-iotests/{222.out => tests/image-fleecing.out} | 0
 2 files changed, 0 insertions(+), 0 deletions(-)
 rename tests/qemu-iotests/{222 => tests/image-fleecing} (100%)
 rename tests/qemu-iotests/{222.out => tests/image-fleecing.out} (100%)

diff --git a/tests/qemu-iotests/222 b/tests/qemu-iotests/tests/image-fleecing
similarity index 100%
rename from tests/qemu-iotests/222
rename to tests/qemu-iotests/tests/image-fleecing
diff --git a/tests/qemu-iotests/222.out b/tests/qemu-iotests/tests/image-fleecing.out
similarity index 100%
rename from tests/qemu-iotests/222.out
rename to tests/qemu-iotests/tests/image-fleecing.out
-- 
2.29.2



^ permalink raw reply	[flat|nested] 47+ messages in thread

* [PATCH v7 29/33] iotests.py: hmp_qemu_io: support qdev
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (27 preceding siblings ...)
  2021-08-04  9:38 ` [PATCH v7 28/33] iotests: move 222 to tests/image-fleecing Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:38 ` Vladimir Sementsov-Ogievskiy
  2021-08-04 16:17   ` John Snow
  2021-08-04  9:38 ` [PATCH v7 30/33] iotests/image-fleecing: proper source device Vladimir Sementsov-Ogievskiy
                   ` (3 subsequent siblings)
  32 siblings, 1 reply; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:38 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 tests/qemu-iotests/iotests.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
index 025e288ddd..9d0031a0e8 100644
--- a/tests/qemu-iotests/iotests.py
+++ b/tests/qemu-iotests/iotests.py
@@ -655,9 +655,10 @@ def resume_drive(self, drive: str) -> None:
         self.hmp(f'qemu-io {drive} "remove_break bp_{drive}"')
 
     def hmp_qemu_io(self, drive: str, cmd: str,
-                    use_log: bool = False) -> QMPMessage:
+                    use_log: bool = False, qdev: bool = False) -> QMPMessage:
         """Write to a given drive using an HMP command"""
-        return self.hmp(f'qemu-io {drive} "{cmd}"', use_log=use_log)
+        d = '-d ' if qdev else ''
+        return self.hmp(f'qemu-io {d}{drive} "{cmd}"', use_log=use_log)
 
     def flatten_qmp_object(self, obj, output=None, basestr=''):
         if output is None:
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 30/33] iotests/image-fleecing: proper source device
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (28 preceding siblings ...)
  2021-08-04  9:38 ` [PATCH v7 29/33] iotests.py: hmp_qemu_io: support qdev Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:38 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:38 ` [PATCH v7 31/33] iotests/image-fleecing: rename tgt_node Vladimir Sementsov-Ogievskiy
                   ` (2 subsequent siblings)
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:38 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

Define scsi device to operate with it by qom-set in further patch.

Give a new node-name to source block node, to not look like device
name.

Job now don't want to work without giving explicit id, so, let's call
it "fleecing".

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 tests/qemu-iotests/tests/image-fleecing     | 12 ++++++++----
 tests/qemu-iotests/tests/image-fleecing.out |  2 +-
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/tests/qemu-iotests/tests/image-fleecing b/tests/qemu-iotests/tests/image-fleecing
index 799369e290..961941bb27 100755
--- a/tests/qemu-iotests/tests/image-fleecing
+++ b/tests/qemu-iotests/tests/image-fleecing
@@ -70,7 +70,11 @@ with iotests.FilePath('base.img') as base_img_path, \
     log('--- Launching VM ---')
     log('')
 
-    vm.add_drive(base_img_path)
+    src_node = 'source'
+    vm.add_blockdev(f'driver={iotests.imgfmt},file.driver=file,'
+                    f'file.filename={base_img_path},node-name={src_node}')
+    vm.add_device('virtio-scsi')
+    vm.add_device(f'scsi-hd,id=sda,drive={src_node}')
     vm.launch()
     log('Done')
 
@@ -78,7 +82,6 @@ with iotests.FilePath('base.img') as base_img_path, \
     log('--- Setting up Fleecing Graph ---')
     log('')
 
-    src_node = 'drive0'
     tgt_node = 'fleeceNode'
 
     # create tgt_node backed by src_node
@@ -94,6 +97,7 @@ with iotests.FilePath('base.img') as base_img_path, \
 
     # Establish COW from source to fleecing node
     log(vm.qmp('blockdev-backup',
+               job_id='fleecing',
                device=src_node,
                target=tgt_node,
                sync='none'))
@@ -125,7 +129,7 @@ with iotests.FilePath('base.img') as base_img_path, \
     for p in overwrite:
         cmd = 'write -P%s %s %s' % p
         log(cmd)
-        log(vm.hmp_qemu_io(src_node, cmd))
+        log(vm.hmp_qemu_io('/machine/peripheral/sda', cmd, qdev=True))
 
     log('')
     log('--- Verifying Data ---')
@@ -140,7 +144,7 @@ with iotests.FilePath('base.img') as base_img_path, \
     log('--- Cleanup ---')
     log('')
 
-    log(vm.qmp('block-job-cancel', device=src_node))
+    log(vm.qmp('block-job-cancel', device='fleecing'))
     e = vm.event_wait('BLOCK_JOB_CANCELLED')
     assert e is not None
     log(e, filters=[iotests.filter_qmp_event])
diff --git a/tests/qemu-iotests/tests/image-fleecing.out b/tests/qemu-iotests/tests/image-fleecing.out
index 16643dde30..314a1b54e9 100644
--- a/tests/qemu-iotests/tests/image-fleecing.out
+++ b/tests/qemu-iotests/tests/image-fleecing.out
@@ -50,7 +50,7 @@ read -P0 0x3fe0000 64k
 --- Cleanup ---
 
 {"return": {}}
-{"data": {"device": "drive0", "len": 67108864, "offset": 393216, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_CANCELLED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
+{"data": {"device": "fleecing", "len": 67108864, "offset": 393216, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_CANCELLED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 {"return": {}}
 {"return": {}}
 
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 31/33] iotests/image-fleecing: rename tgt_node
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (29 preceding siblings ...)
  2021-08-04  9:38 ` [PATCH v7 30/33] iotests/image-fleecing: proper source device Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:38 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:38 ` [PATCH v7 32/33] iotests/image-fleecing: prepare for adding new test-case Vladimir Sementsov-Ogievskiy
  2021-08-04  9:38 ` [PATCH v7 33/33] iotests/image-fleecing: add test-case for copy-before-write filter Vladimir Sementsov-Ogievskiy
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:38 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

Actually target of backup(sync=None) is not a final backup target:
image fleecing is intended to be used with external tool, which will
copy data from fleecing node to some real backup target.

Also, we are going to add a test case for "push backup with fleecing",
where instead of exporting fleecing node by NBD, we'll start a backup
job from fleecing node to real backup target.

To avoid confusion, let's rename temporary fleecing node now.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 tests/qemu-iotests/tests/image-fleecing | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/tests/qemu-iotests/tests/image-fleecing b/tests/qemu-iotests/tests/image-fleecing
index 961941bb27..ec4ef5f3f6 100755
--- a/tests/qemu-iotests/tests/image-fleecing
+++ b/tests/qemu-iotests/tests/image-fleecing
@@ -71,6 +71,7 @@ with iotests.FilePath('base.img') as base_img_path, \
     log('')
 
     src_node = 'source'
+    tmp_node = 'temp'
     vm.add_blockdev(f'driver={iotests.imgfmt},file.driver=file,'
                     f'file.filename={base_img_path},node-name={src_node}')
     vm.add_device('virtio-scsi')
@@ -82,12 +83,11 @@ with iotests.FilePath('base.img') as base_img_path, \
     log('--- Setting up Fleecing Graph ---')
     log('')
 
-    tgt_node = 'fleeceNode'
 
-    # create tgt_node backed by src_node
+    # create tmp_node backed by src_node
     log(vm.qmp('blockdev-add', {
         'driver': 'qcow2',
-        'node-name': tgt_node,
+        'node-name': tmp_node,
         'file': {
             'driver': 'file',
             'filename': fleece_img_path,
@@ -99,19 +99,19 @@ with iotests.FilePath('base.img') as base_img_path, \
     log(vm.qmp('blockdev-backup',
                job_id='fleecing',
                device=src_node,
-               target=tgt_node,
+               target=tmp_node,
                sync='none'))
 
     log('')
     log('--- Setting up NBD Export ---')
     log('')
 
-    nbd_uri = 'nbd+unix:///%s?socket=%s' % (tgt_node, nbd_sock_path)
+    nbd_uri = 'nbd+unix:///%s?socket=%s' % (tmp_node, nbd_sock_path)
     log(vm.qmp('nbd-server-start',
                {'addr': { 'type': 'unix',
                           'data': { 'path': nbd_sock_path } } }))
 
-    log(vm.qmp('nbd-server-add', device=tgt_node))
+    log(vm.qmp('nbd-server-add', device=tmp_node))
 
     log('')
     log('--- Sanity Check ---')
@@ -149,7 +149,7 @@ with iotests.FilePath('base.img') as base_img_path, \
     assert e is not None
     log(e, filters=[iotests.filter_qmp_event])
     log(vm.qmp('nbd-server-stop'))
-    log(vm.qmp('blockdev-del', node_name=tgt_node))
+    log(vm.qmp('blockdev-del', node_name=tmp_node))
     vm.shutdown()
 
     log('')
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 32/33] iotests/image-fleecing: prepare for adding new test-case
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (30 preceding siblings ...)
  2021-08-04  9:38 ` [PATCH v7 31/33] iotests/image-fleecing: rename tgt_node Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:38 ` Vladimir Sementsov-Ogievskiy
  2021-08-04  9:38 ` [PATCH v7 33/33] iotests/image-fleecing: add test-case for copy-before-write filter Vladimir Sementsov-Ogievskiy
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:38 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

We are going to add a test-case with some behavior modifications. So,
let's prepare a function to be reused.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 tests/qemu-iotests/tests/image-fleecing | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/tests/qemu-iotests/tests/image-fleecing b/tests/qemu-iotests/tests/image-fleecing
index ec4ef5f3f6..e210c00d28 100755
--- a/tests/qemu-iotests/tests/image-fleecing
+++ b/tests/qemu-iotests/tests/image-fleecing
@@ -48,12 +48,7 @@ remainder = [('0xd5', '0x108000',  '32k'), # Right-end of partial-left [1]
              ('0xdc', '32M',       '32k'), # Left-end of partial-right [2]
              ('0xcd', '0x3ff0000', '64k')] # patterns[3]
 
-with iotests.FilePath('base.img') as base_img_path, \
-     iotests.FilePath('fleece.img') as fleece_img_path, \
-     iotests.FilePath('nbd.sock',
-                      base_dir=iotests.sock_dir) as nbd_sock_path, \
-     iotests.VM() as vm:
-
+def do_test(base_img_path, fleece_img_path, nbd_sock_path, vm):
     log('--- Setting up images ---')
     log('')
 
@@ -163,3 +158,15 @@ with iotests.FilePath('base.img') as base_img_path, \
 
     log('')
     log('Done')
+
+
+def test():
+    with iotests.FilePath('base.img') as base_img_path, \
+         iotests.FilePath('fleece.img') as fleece_img_path, \
+         iotests.FilePath('nbd.sock',
+                          base_dir=iotests.sock_dir) as nbd_sock_path, \
+         iotests.VM() as vm:
+        do_test(base_img_path, fleece_img_path, nbd_sock_path, vm)
+
+
+test()
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* [PATCH v7 33/33] iotests/image-fleecing: add test-case for copy-before-write filter
  2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
                   ` (31 preceding siblings ...)
  2021-08-04  9:38 ` [PATCH v7 32/33] iotests/image-fleecing: prepare for adding new test-case Vladimir Sementsov-Ogievskiy
@ 2021-08-04  9:38 ` Vladimir Sementsov-Ogievskiy
  32 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-04  9:38 UTC (permalink / raw)
  To: qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	vsementsov, jsnow, mreitz, kwolf

New fleecing method becomes available: copy-before-write filter.

Actually we don't need backup job to setup image fleecing. Add test
for new recommended way of image fleecing.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
---
 tests/qemu-iotests/tests/image-fleecing     | 50 +++++++++-----
 tests/qemu-iotests/tests/image-fleecing.out | 72 +++++++++++++++++++++
 2 files changed, 107 insertions(+), 15 deletions(-)

diff --git a/tests/qemu-iotests/tests/image-fleecing b/tests/qemu-iotests/tests/image-fleecing
index e210c00d28..f6318492c6 100755
--- a/tests/qemu-iotests/tests/image-fleecing
+++ b/tests/qemu-iotests/tests/image-fleecing
@@ -48,7 +48,7 @@ remainder = [('0xd5', '0x108000',  '32k'), # Right-end of partial-left [1]
              ('0xdc', '32M',       '32k'), # Left-end of partial-right [2]
              ('0xcd', '0x3ff0000', '64k')] # patterns[3]
 
-def do_test(base_img_path, fleece_img_path, nbd_sock_path, vm):
+def do_test(use_cbw, base_img_path, fleece_img_path, nbd_sock_path, vm):
     log('--- Setting up images ---')
     log('')
 
@@ -67,6 +67,7 @@ def do_test(base_img_path, fleece_img_path, nbd_sock_path, vm):
 
     src_node = 'source'
     tmp_node = 'temp'
+    qom_path = '/machine/peripheral/sda'
     vm.add_blockdev(f'driver={iotests.imgfmt},file.driver=file,'
                     f'file.filename={base_img_path},node-name={src_node}')
     vm.add_device('virtio-scsi')
@@ -90,12 +91,22 @@ def do_test(base_img_path, fleece_img_path, nbd_sock_path, vm):
         'backing': src_node,
     }))
 
-    # Establish COW from source to fleecing node
-    log(vm.qmp('blockdev-backup',
-               job_id='fleecing',
-               device=src_node,
-               target=tmp_node,
-               sync='none'))
+    # Establish CBW from source to fleecing node
+    if use_cbw:
+        log(vm.qmp('blockdev-add', {
+            'driver': 'copy-before-write',
+            'node-name': 'fl-cbw',
+            'file': src_node,
+            'target': tmp_node
+        }))
+
+        log(vm.qmp('qom-set', path=qom_path, property='drive', value='fl-cbw'))
+    else:
+        log(vm.qmp('blockdev-backup',
+                   job_id='fleecing',
+                   device=src_node,
+                   target=tmp_node,
+                   sync='none'))
 
     log('')
     log('--- Setting up NBD Export ---')
@@ -124,7 +135,7 @@ def do_test(base_img_path, fleece_img_path, nbd_sock_path, vm):
     for p in overwrite:
         cmd = 'write -P%s %s %s' % p
         log(cmd)
-        log(vm.hmp_qemu_io('/machine/peripheral/sda', cmd, qdev=True))
+        log(vm.hmp_qemu_io(qom_path, cmd, qdev=True))
 
     log('')
     log('--- Verifying Data ---')
@@ -139,10 +150,15 @@ def do_test(base_img_path, fleece_img_path, nbd_sock_path, vm):
     log('--- Cleanup ---')
     log('')
 
-    log(vm.qmp('block-job-cancel', device='fleecing'))
-    e = vm.event_wait('BLOCK_JOB_CANCELLED')
-    assert e is not None
-    log(e, filters=[iotests.filter_qmp_event])
+    if use_cbw:
+        log(vm.qmp('qom-set', path=qom_path, property='drive', value=src_node))
+        log(vm.qmp('blockdev-del', node_name='fl-cbw'))
+    else:
+        log(vm.qmp('block-job-cancel', device='fleecing'))
+        e = vm.event_wait('BLOCK_JOB_CANCELLED')
+        assert e is not None
+        log(e, filters=[iotests.filter_qmp_event])
+
     log(vm.qmp('nbd-server-stop'))
     log(vm.qmp('blockdev-del', node_name=tmp_node))
     vm.shutdown()
@@ -160,13 +176,17 @@ def do_test(base_img_path, fleece_img_path, nbd_sock_path, vm):
     log('Done')
 
 
-def test():
+def test(use_cbw):
     with iotests.FilePath('base.img') as base_img_path, \
          iotests.FilePath('fleece.img') as fleece_img_path, \
          iotests.FilePath('nbd.sock',
                           base_dir=iotests.sock_dir) as nbd_sock_path, \
          iotests.VM() as vm:
-        do_test(base_img_path, fleece_img_path, nbd_sock_path, vm)
+        do_test(use_cbw, base_img_path, fleece_img_path, nbd_sock_path, vm)
+
 
+log('=== Test backup(sync=none) based fleecing ===\n')
+test(False)
 
-test()
+log('=== Test filter based fleecing ===\n')
+test(True)
diff --git a/tests/qemu-iotests/tests/image-fleecing.out b/tests/qemu-iotests/tests/image-fleecing.out
index 314a1b54e9..e96d122a8b 100644
--- a/tests/qemu-iotests/tests/image-fleecing.out
+++ b/tests/qemu-iotests/tests/image-fleecing.out
@@ -1,3 +1,5 @@
+=== Test backup(sync=none) based fleecing ===
+
 --- Setting up images ---
 
 Done
@@ -65,3 +67,73 @@ read -P0xdc 32M 32k
 read -P0xcd 0x3ff0000 64k
 
 Done
+=== Test filter based fleecing ===
+
+--- Setting up images ---
+
+Done
+
+--- Launching VM ---
+
+Done
+
+--- Setting up Fleecing Graph ---
+
+{"return": {}}
+{"return": {}}
+{"return": {}}
+
+--- Setting up NBD Export ---
+
+{"return": {}}
+{"return": {}}
+
+--- Sanity Check ---
+
+read -P0x5d 0 64k
+read -P0xd5 1M 64k
+read -P0xdc 32M 64k
+read -P0xcd 0x3ff0000 64k
+read -P0 0x00f8000 32k
+read -P0 0x2010000 32k
+read -P0 0x3fe0000 64k
+
+--- Testing COW ---
+
+write -P0xab 0 64k
+{"return": ""}
+write -P0xad 0x00f8000 64k
+{"return": ""}
+write -P0x1d 0x2008000 64k
+{"return": ""}
+write -P0xea 0x3fe0000 64k
+{"return": ""}
+
+--- Verifying Data ---
+
+read -P0x5d 0 64k
+read -P0xd5 1M 64k
+read -P0xdc 32M 64k
+read -P0xcd 0x3ff0000 64k
+read -P0 0x00f8000 32k
+read -P0 0x2010000 32k
+read -P0 0x3fe0000 64k
+
+--- Cleanup ---
+
+{"return": {}}
+{"return": {}}
+{"return": {}}
+{"return": {}}
+
+--- Confirming writes ---
+
+read -P0xab 0 64k
+read -P0xad 0x00f8000 64k
+read -P0x1d 0x2008000 64k
+read -P0xea 0x3fe0000 64k
+read -P0xd5 0x108000 32k
+read -P0xdc 32M 32k
+read -P0xcd 0x3ff0000 64k
+
+Done
-- 
2.29.2



^ permalink raw reply related	[flat|nested] 47+ messages in thread

* Re: [PATCH v7 22/33] qapi: publish copy-before-write filter
  2021-08-04  9:38 ` [PATCH v7 22/33] qapi: publish copy-before-write filter Vladimir Sementsov-Ogievskiy
@ 2021-08-04 13:18   ` Markus Armbruster
  0 siblings, 0 replies; 47+ messages in thread
From: Markus Armbruster @ 2021-08-04 13:18 UTC (permalink / raw)
  To: Vladimir Sementsov-Ogievskiy
  Cc: kwolf, berrange, ehabkost, qemu-block, jsnow, qemu-devel, mreitz,
	crosa, pbonzini, eblake

Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> writes:

> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> Reviewed-by: Max Reitz <mreitz@redhat.com>
> ---
>  qapi/block-core.json | 25 +++++++++++++++++++++++--
>  1 file changed, 23 insertions(+), 2 deletions(-)
>
> diff --git a/qapi/block-core.json b/qapi/block-core.json
> index 675d8265eb..59d3e5e42d 100644
> --- a/qapi/block-core.json
> +++ b/qapi/block-core.json
> @@ -2825,13 +2825,14 @@
>  # @blklogwrites: Since 3.0
>  # @blkreplay: Since 4.2
>  # @compress: Since 5.0
> +# @copy-before-write: Since 6.1
>  #
>  # Since: 2.9
>  ##
>  { 'enum': 'BlockdevDriver',
>    'data': [ 'blkdebug', 'blklogwrites', 'blkreplay', 'blkverify', 'bochs',
> -            'cloop', 'compress', 'copy-on-read', 'dmg', 'file', 'ftp', 'ftps',
> -            'gluster',
> +            'cloop', 'compress', 'copy-before-write', 'copy-on-read', 'dmg',
> +            'file', 'ftp', 'ftps', 'gluster',
>              {'name': 'host_cdrom', 'if': 'defined(HAVE_HOST_BLOCK_DEVICE)' },
>              {'name': 'host_device', 'if': 'defined(HAVE_HOST_BLOCK_DEVICE)' },
>              'http', 'https', 'iscsi',
> @@ -4049,6 +4050,25 @@
>    'base': 'BlockdevOptionsGenericFormat',
>    'data': { '*bottom': 'str' } }
>  
> +##
> +# @BlockdevOptionsCbw:
> +#
> +# Driver specific block device options for the copy-before-write driver,
> +# which does so called copy-before-write operations: when data is
> +# written to the filter, the filter firstly reads corresponding blocks

s/firstly/first/

> +# from its file child and copies them to @target child. After successful

s/successful/successfully/

> +# copying the write request is propagated to file child. If copying

Comma after copying, I think.

> +# failed, the original write request is failed too and no data is written

s/failed,/fails,/

> +# to file child.
> +#
> +# @target: The target for copy-before-write operations.
> +#
> +# Since: 6.1
> +##
> +{ 'struct': 'BlockdevOptionsCbw',
> +  'base': 'BlockdevOptionsGenericFormat',
> +  'data': { 'target': 'BlockdevRef' } }
> +
>  ##
>  # @BlockdevOptions:
>  #
> @@ -4101,6 +4121,7 @@
>        'bochs':      'BlockdevOptionsGenericFormat',
>        'cloop':      'BlockdevOptionsGenericFormat',
>        'compress':   'BlockdevOptionsGenericFormat',
> +      'copy-before-write':'BlockdevOptionsCbw',
>        'copy-on-read':'BlockdevOptionsCor',
>        'dmg':        'BlockdevOptionsGenericFormat',
>        'file':       'BlockdevOptionsFile',

With the doc phrasing tweaks duly considered:
Acked-by: Markus Armbruster <armbru@redhat.com>



^ permalink raw reply	[flat|nested] 47+ messages in thread

* Re: [PATCH v7 29/33] iotests.py: hmp_qemu_io: support qdev
  2021-08-04  9:38 ` [PATCH v7 29/33] iotests.py: hmp_qemu_io: support qdev Vladimir Sementsov-Ogievskiy
@ 2021-08-04 16:17   ` John Snow
  0 siblings, 0 replies; 47+ messages in thread
From: John Snow @ 2021-08-04 16:17 UTC (permalink / raw)
  To: Vladimir Sementsov-Ogievskiy
  Cc: Kevin Wolf, Daniel Berrange, Eduardo Habkost, qemu-block,
	qemu-devel, Markus Armbruster, Cleber Rosa, Paolo Bonzini,
	Max Reitz, Eric Blake

[-- Attachment #1: Type: text/plain, Size: 1396 bytes --]

On Wed, Aug 4, 2021 at 5:39 AM Vladimir Sementsov-Ogievskiy <
vsementsov@virtuozzo.com> wrote:

> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> Reviewed-by: Max Reitz <mreitz@redhat.com>
> ---
>  tests/qemu-iotests/iotests.py | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
> index 025e288ddd..9d0031a0e8 100644
> --- a/tests/qemu-iotests/iotests.py
> +++ b/tests/qemu-iotests/iotests.py
> @@ -655,9 +655,10 @@ def resume_drive(self, drive: str) -> None:
>          self.hmp(f'qemu-io {drive} "remove_break bp_{drive}"')
>
>      def hmp_qemu_io(self, drive: str, cmd: str,
> -                    use_log: bool = False) -> QMPMessage:
> +                    use_log: bool = False, qdev: bool = False) ->
> QMPMessage:
>          """Write to a given drive using an HMP command"""
> -        return self.hmp(f'qemu-io {drive} "{cmd}"', use_log=use_log)
> +        d = '-d ' if qdev else ''
> +        return self.hmp(f'qemu-io {d}{drive} "{cmd}"', use_log=use_log)
>
>      def flatten_qmp_object(self, obj, output=None, basestr=''):
>          if output is None:
> --
> 2.29.2
>
>
Guess that's really the only flag that this HMP command supports. I was
gonna suggest abstracting to {args} ... but, uh, that's the only one, so...
sure!

Reviewed-by: John Snow <jsnow@redhat.com>

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^ permalink raw reply	[flat|nested] 47+ messages in thread

* Re: [PATCH v7 25/33] iotests.py: VM: add own __enter__ method
  2021-08-04  9:38 ` [PATCH v7 25/33] iotests.py: VM: add own __enter__ method Vladimir Sementsov-Ogievskiy
@ 2021-08-04 16:27   ` John Snow
  2021-08-23 17:22     ` Vladimir Sementsov-Ogievskiy
  0 siblings, 1 reply; 47+ messages in thread
From: John Snow @ 2021-08-04 16:27 UTC (permalink / raw)
  To: Vladimir Sementsov-Ogievskiy
  Cc: Kevin Wolf, Daniel Berrange, Eduardo Habkost, qemu-block,
	qemu-devel, Markus Armbruster, Cleber Rosa, Paolo Bonzini,
	Max Reitz, Eric Blake

[-- Attachment #1: Type: text/plain, Size: 2559 bytes --]

On Wed, Aug 4, 2021 at 5:39 AM Vladimir Sementsov-Ogievskiy <
vsementsov@virtuozzo.com> wrote:

> In superclass __enter__ method is defined with return value type hint
> 'QEMUMachine'. So, mypy thinks that return value of VM.__enter__ is
> QEMUMachine. Let's redefine __enter__ in VM class, to give it correct
> type hint.
>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> Reviewed-by: Max Reitz <mreitz@redhat.com>
> ---
>  tests/qemu-iotests/iotests.py | 4 ++++
>  1 file changed, 4 insertions(+)
>
> diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
> index 89663dac06..025e288ddd 100644
> --- a/tests/qemu-iotests/iotests.py
> +++ b/tests/qemu-iotests/iotests.py
> @@ -568,6 +568,10 @@ def remote_filename(path):
>  class VM(qtest.QEMUQtestMachine):
>      '''A QEMU VM'''
>
> +    # Redefine __enter__ with proper type hint
> +    def __enter__(self) -> 'VM':
> +        return self
> +
>      def __init__(self, path_suffix=''):
>          name = "qemu%s-%d" % (path_suffix, os.getpid())
>          super().__init__(qemu_prog, qemu_opts, name=name,
> --
> 2.29.2
>

First and foremost:

Reviewed-by: John Snow <jsnow@redhat.com>
Acked-by: John Snow <jsnow@redhat.com>

A more durable approach might be to annotate QEMUMachine differently such
that subclasses get the right types automatically. See if this following
snippet works instead of adding a new __enter__ method.

diff --git a/python/qemu/machine/machine.py b/python/qemu/machine/machine.py
index 971ed7e8c6a..2e410103569 100644
--- a/python/qemu/machine/machine.py
+++ b/python/qemu/machine/machine.py
@@ -36,6 +36,7 @@
     Sequence,
     Tuple,
     Type,
+    TypeVar,
 )

 from qemu.qmp import (  # pylint: disable=import-error
@@ -73,6 +74,9 @@ class AbnormalShutdown(QEMUMachineError):
     """


+_T = TypeVar('_T', bound='QEMUMachine')
+
+
 class QEMUMachine:
     """
     A QEMU VM.
@@ -166,7 +170,7 @@ def __init__(self,
         self._remove_files: List[str] = []
         self._user_killed = False

-    def __enter__(self) -> 'QEMUMachine':
+    def __enter__(self: _T) -> _T:
         return self

     def __exit__(self,
@@ -182,8 +186,8 @@ def add_monitor_null(self) -> None:
         self._args.append('-monitor')
         self._args.append('null')

-    def add_fd(self, fd: int, fdset: int,
-               opaque: str, opts: str = '') -> 'QEMUMachine':
+    def add_fd(self: _T, fd: int, fdset: int,
+               opaque: str, opts: str = '') -> _T:
         """
         Pass a file descriptor to the VM
         """

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^ permalink raw reply related	[flat|nested] 47+ messages in thread

* Re: [PATCH v7 06/33] block-copy: move detecting fleecing scheme to block-copy
  2021-08-04  9:37 ` [PATCH v7 06/33] block-copy: move detecting fleecing scheme to block-copy Vladimir Sementsov-Ogievskiy
@ 2021-08-10 14:44   ` Hanna Reitz
  0 siblings, 0 replies; 47+ messages in thread
From: Hanna Reitz @ 2021-08-10 14:44 UTC (permalink / raw)
  To: Vladimir Sementsov-Ogievskiy, qemu-block
  Cc: kwolf, berrange, ehabkost, jsnow, qemu-devel, armbru, crosa,
	pbonzini, mreitz, eblake

On 04.08.21 11:37, Vladimir Sementsov-Ogievskiy wrote:
> We want to simplify initialization interface of copy-before-write
> filter as we are going to make it public. So, let's detect fleecing
> scheme exactly in block-copy code, to not pass this information through
> extra levels.
>
> Why not just set BDRV_REQ_SERIALISING unconditionally: because we are
> going to implement new more efficient fleecing scheme which will not
> rely on backing feature.
>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
>   block/copy-before-write.h  |  2 +-
>   include/block/block-copy.h |  3 +--
>   block/backup.c             | 21 +--------------------
>   block/block-copy.c         | 24 +++++++++++++++++++++---
>   block/copy-before-write.c  |  4 ++--
>   5 files changed, 26 insertions(+), 28 deletions(-)

Reviewed-by: Hanna Reitz <hreitz@redhat.com>



^ permalink raw reply	[flat|nested] 47+ messages in thread

* Re: [PATCH v7 07/33] block/block-copy: introduce block_copy_set_copy_opts()
  2021-08-04  9:37 ` [PATCH v7 07/33] block/block-copy: introduce block_copy_set_copy_opts() Vladimir Sementsov-Ogievskiy
@ 2021-08-10 14:55   ` Hanna Reitz
  2021-08-23 12:05     ` Vladimir Sementsov-Ogievskiy
  0 siblings, 1 reply; 47+ messages in thread
From: Hanna Reitz @ 2021-08-10 14:55 UTC (permalink / raw)
  To: Vladimir Sementsov-Ogievskiy, qemu-block
  Cc: kwolf, berrange, ehabkost, jsnow, qemu-devel, armbru, crosa,
	pbonzini, mreitz, eblake

On 04.08.21 11:37, Vladimir Sementsov-Ogievskiy wrote:
> We'll need a possibility to set compress and use_copy_range options
> after initialization of the state. So make corresponding part of
> block_copy_state_new() separate and public.
>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
>   include/block/block-copy.h |  2 ++
>   block/block-copy.c         | 66 +++++++++++++++++++++-----------------
>   2 files changed, 39 insertions(+), 29 deletions(-)
>
> diff --git a/include/block/block-copy.h b/include/block/block-copy.h
> index 734389d32a..f0ba7bc828 100644
> --- a/include/block/block-copy.h
> +++ b/include/block/block-copy.h
> @@ -28,6 +28,8 @@ BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
>                                        int64_t cluster_size, bool use_copy_range,
>                                        bool compress, Error **errp);
>   
> +void block_copy_set_copy_opts(BlockCopyState *s, bool use_copy_range,
> +                              bool compress);
>   void block_copy_set_progress_meter(BlockCopyState *s, ProgressMeter *pm);
>   
>   void block_copy_state_free(BlockCopyState *s);
> diff --git a/block/block-copy.c b/block/block-copy.c
> index 58b4345a5a..84c29fb233 100644
> --- a/block/block-copy.c
> +++ b/block/block-copy.c
> @@ -315,21 +315,11 @@ static uint32_t block_copy_max_transfer(BdrvChild *source, BdrvChild *target)
>                                        target->bs->bl.max_transfer));
>   }
>   
> -BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
> -                                     int64_t cluster_size, bool use_copy_range,
> -                                     bool compress, Error **errp)
> +/* Function should be called prior any actual copy request */

Given this is something the caller should know, I’d prefer putting this 
into the block-copy.h header.

However, I realize we have a wild mix of this in qemu and often do put 
such information into the C source file, so...

> +void block_copy_set_copy_opts(BlockCopyState *s, bool use_copy_range,
> +                              bool compress)
>   {
> -    BlockCopyState *s;
> -    BdrvDirtyBitmap *copy_bitmap;
>       bool is_fleecing;
> -
> -    copy_bitmap = bdrv_create_dirty_bitmap(source->bs, cluster_size, NULL,
> -                                           errp);
> -    if (!copy_bitmap) {
> -        return NULL;
> -    }
> -    bdrv_disable_dirty_bitmap(copy_bitmap);
> -
>       /*
>        * 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
> @@ -344,24 +334,12 @@ BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
>        * For more information see commit f8d59dfb40bb and test
>        * tests/qemu-iotests/222
>        */
> -    is_fleecing = bdrv_chain_contains(target->bs, source->bs);
> +    is_fleecing = bdrv_chain_contains(s->target->bs, s->source->bs);
>   
> -    s = g_new(BlockCopyState, 1);
> -    *s = (BlockCopyState) {
> -        .source = source,
> -        .target = target,
> -        .copy_bitmap = copy_bitmap,
> -        .cluster_size = cluster_size,
> -        .len = bdrv_dirty_bitmap_size(copy_bitmap),
> -        .write_flags = (is_fleecing ? BDRV_REQ_SERIALISING : 0) |
> -            (compress ? BDRV_REQ_WRITE_COMPRESSED : 0),
> -        .mem = shres_create(BLOCK_COPY_MAX_MEM),
> -        .max_transfer = QEMU_ALIGN_DOWN(
> -                                    block_copy_max_transfer(source, target),
> -                                    cluster_size),
> -    };
> +    s->write_flags = (is_fleecing ? BDRV_REQ_SERIALISING : 0) |
> +        (compress ? BDRV_REQ_WRITE_COMPRESSED : 0);

Shouldn’t we keep the is_fleecing check in block_copy_state_new()? We 
must perform it at least once, but there is no benefit in repeating it 
on every block_copy_set_copy_opts() call, right?

Hanna



^ permalink raw reply	[flat|nested] 47+ messages in thread

* Re: [PATCH v7 08/33] block/backup: set copy_range and compress after filter insertion
  2021-08-04  9:37 ` [PATCH v7 08/33] block/backup: set copy_range and compress after filter insertion Vladimir Sementsov-Ogievskiy
@ 2021-08-10 15:07   ` Hanna Reitz
  0 siblings, 0 replies; 47+ messages in thread
From: Hanna Reitz @ 2021-08-10 15:07 UTC (permalink / raw)
  To: Vladimir Sementsov-Ogievskiy, qemu-block
  Cc: kwolf, berrange, ehabkost, jsnow, qemu-devel, armbru, crosa,
	pbonzini, mreitz, eblake

On 04.08.21 11:37, Vladimir Sementsov-Ogievskiy wrote:
> We are going to publish copy-before-write filter, so it would be
> initialized through options. Still we don't want to publish compress
> and copy-range options, as
>
> 1. Modern way to enable compression is to use compress filter.
>
> 2. For copy-range it's unclean how to make proper interface:
>   - it's has experimental prefix for backup job anyway
>   - the whole BackupPerf structure doesn't make sense for the filter
>   So, let's just add copy-range possibility to the filter later if
>   needed.
>
> Still, we are going to continue support for compression and
> experimental copy-range in backup job. So, set these options after
> filter creation.
>
> Note, that we can drop "compress" argument of bdrv_cbw_append() now, as
> well as "perf". The only reason not doing so is that now, when I
> prepare this patch the big series around it is already reviewed and I
> want to avoid extra rebase conflicts to simplify review of the
> following version.
>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
>   block/copy-before-write.h | 1 -
>   block/backup.c            | 3 ++-
>   block/copy-before-write.c | 4 +---
>   3 files changed, 3 insertions(+), 5 deletions(-)

Reviewed-by: Hanna Reitz <hreitz@redhat.com>



^ permalink raw reply	[flat|nested] 47+ messages in thread

* Re: [PATCH v7 17/33] block/copy-before-write: bdrv_cbw_append(): drop unused compress arg
  2021-08-04  9:37 ` [PATCH v7 17/33] block/copy-before-write: bdrv_cbw_append(): drop unused compress arg Vladimir Sementsov-Ogievskiy
@ 2021-08-10 15:17   ` Hanna Reitz
  2021-08-23 16:33     ` Vladimir Sementsov-Ogievskiy
  0 siblings, 1 reply; 47+ messages in thread
From: Hanna Reitz @ 2021-08-10 15:17 UTC (permalink / raw)
  To: Vladimir Sementsov-Ogievskiy, qemu-block
  Cc: kwolf, berrange, ehabkost, jsnow, qemu-devel, armbru, crosa,
	pbonzini, mreitz, eblake

On 04.08.21 11:37, Vladimir Sementsov-Ogievskiy wrote:
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
>   block/copy-before-write.h | 1 -
>   block/backup.c            | 2 +-
>   block/copy-before-write.c | 7 +++----
>   3 files changed, 4 insertions(+), 6 deletions(-)

Well, I mean, it isn’t exactly syntactically unused before this patch; 
it’s only unused because this patch drops it from cbw_init(), too.

It definitely is functionally unused, though, so:

Reviewed-by: Hanna Reitz <hreitz@redhat.com>

I wonder whether we should drop @use_copy_range and @compress from 
block_copy_state_new(), too, though.

Hanna



^ permalink raw reply	[flat|nested] 47+ messages in thread

* Re: [PATCH v7 18/33] block/copy-before-write: cbw_init(): use options
  2021-08-04  9:37 ` [PATCH v7 18/33] block/copy-before-write: cbw_init(): use options Vladimir Sementsov-Ogievskiy
@ 2021-08-10 15:18   ` Hanna Reitz
  0 siblings, 0 replies; 47+ messages in thread
From: Hanna Reitz @ 2021-08-10 15:18 UTC (permalink / raw)
  To: Vladimir Sementsov-Ogievskiy, qemu-block
  Cc: kwolf, berrange, ehabkost, jsnow, qemu-devel, armbru, crosa,
	pbonzini, mreitz, eblake

On 04.08.21 11:37, Vladimir Sementsov-Ogievskiy wrote:
> One more step closer to .bdrv_open(): use options instead of plain
> arguments. Move to bdrv_open_child() calls, native for drive open
> handlers.
>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
>   block/copy-before-write.c | 29 +++++++++++++++--------------
>   1 file changed, 15 insertions(+), 14 deletions(-)

Reviewed-by: Hanna Reitz <hreitz@redhat.com>



^ permalink raw reply	[flat|nested] 47+ messages in thread

* Re: [PATCH v7 20/33] block/block-copy: make setting progress optional
  2021-08-04  9:38 ` [PATCH v7 20/33] block/block-copy: make setting progress optional Vladimir Sementsov-Ogievskiy
@ 2021-08-10 15:23   ` Hanna Reitz
  0 siblings, 0 replies; 47+ messages in thread
From: Hanna Reitz @ 2021-08-10 15:23 UTC (permalink / raw)
  To: Vladimir Sementsov-Ogievskiy, qemu-block
  Cc: kwolf, berrange, ehabkost, jsnow, qemu-devel, armbru, crosa,
	pbonzini, mreitz, eblake

On 04.08.21 11:38, Vladimir Sementsov-Ogievskiy wrote:
> Now block-copy will crash if user don't set progress meter by
> block_copy_set_progress_meter(). copy-before-write filter will be used
> in separate of backup job, and it doesn't want any progress meter (for
> now). So, allow not setting it.
>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> Reviewed-by: Max Reitz <mreitz@redhat.com>
> ---
>   block/block-copy.c | 18 +++++++++++-------
>   1 file changed, 11 insertions(+), 7 deletions(-)

(Sorry for the accidental reply to v2...  I’ll just repeat myself:)

OK, looks a bit different from when I last reviewed this, because of the 
rebase on e3dd339feec2da3bcd82021e4ce4fe09dbf9c8b4, but R-b stands.

Hanna



^ permalink raw reply	[flat|nested] 47+ messages in thread

* Re: [PATCH v7 07/33] block/block-copy: introduce block_copy_set_copy_opts()
  2021-08-10 14:55   ` Hanna Reitz
@ 2021-08-23 12:05     ` Vladimir Sementsov-Ogievskiy
  2021-08-23 17:40       ` Vladimir Sementsov-Ogievskiy
  0 siblings, 1 reply; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-23 12:05 UTC (permalink / raw)
  To: Hanna Reitz, qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	jsnow, mreitz, kwolf

10.08.2021 17:55, Hanna Reitz wrote:
> On 04.08.21 11:37, Vladimir Sementsov-Ogievskiy wrote:
>> We'll need a possibility to set compress and use_copy_range options
>> after initialization of the state. So make corresponding part of
>> block_copy_state_new() separate and public.
>>
>> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
>> ---
>>   include/block/block-copy.h |  2 ++
>>   block/block-copy.c         | 66 +++++++++++++++++++++-----------------
>>   2 files changed, 39 insertions(+), 29 deletions(-)
>>
>> diff --git a/include/block/block-copy.h b/include/block/block-copy.h
>> index 734389d32a..f0ba7bc828 100644
>> --- a/include/block/block-copy.h
>> +++ b/include/block/block-copy.h
>> @@ -28,6 +28,8 @@ BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
>>                                        int64_t cluster_size, bool use_copy_range,
>>                                        bool compress, Error **errp);
>> +void block_copy_set_copy_opts(BlockCopyState *s, bool use_copy_range,
>> +                              bool compress);
>>   void block_copy_set_progress_meter(BlockCopyState *s, ProgressMeter *pm);
>>   void block_copy_state_free(BlockCopyState *s);
>> diff --git a/block/block-copy.c b/block/block-copy.c
>> index 58b4345a5a..84c29fb233 100644
>> --- a/block/block-copy.c
>> +++ b/block/block-copy.c
>> @@ -315,21 +315,11 @@ static uint32_t block_copy_max_transfer(BdrvChild *source, BdrvChild *target)
>>                                        target->bs->bl.max_transfer));
>>   }
>> -BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
>> -                                     int64_t cluster_size, bool use_copy_range,
>> -                                     bool compress, Error **errp)
>> +/* Function should be called prior any actual copy request */
> 
> Given this is something the caller should know, I’d prefer putting this into the block-copy.h header.
> 
> However, I realize we have a wild mix of this in qemu and often do put such information into the C source file, so...
> 
>> +void block_copy_set_copy_opts(BlockCopyState *s, bool use_copy_range,
>> +                              bool compress)
>>   {
>> -    BlockCopyState *s;
>> -    BdrvDirtyBitmap *copy_bitmap;
>>       bool is_fleecing;
>> -
>> -    copy_bitmap = bdrv_create_dirty_bitmap(source->bs, cluster_size, NULL,
>> -                                           errp);
>> -    if (!copy_bitmap) {
>> -        return NULL;
>> -    }
>> -    bdrv_disable_dirty_bitmap(copy_bitmap);
>> -
>>       /*
>>        * 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
>> @@ -344,24 +334,12 @@ BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
>>        * For more information see commit f8d59dfb40bb and test
>>        * tests/qemu-iotests/222
>>        */
>> -    is_fleecing = bdrv_chain_contains(target->bs, source->bs);
>> +    is_fleecing = bdrv_chain_contains(s->target->bs, s->source->bs);
>> -    s = g_new(BlockCopyState, 1);
>> -    *s = (BlockCopyState) {
>> -        .source = source,
>> -        .target = target,
>> -        .copy_bitmap = copy_bitmap,
>> -        .cluster_size = cluster_size,
>> -        .len = bdrv_dirty_bitmap_size(copy_bitmap),
>> -        .write_flags = (is_fleecing ? BDRV_REQ_SERIALISING : 0) |
>> -            (compress ? BDRV_REQ_WRITE_COMPRESSED : 0),
>> -        .mem = shres_create(BLOCK_COPY_MAX_MEM),
>> -        .max_transfer = QEMU_ALIGN_DOWN(
>> -                                    block_copy_max_transfer(source, target),
>> -                                    cluster_size),
>> -    };
>> +    s->write_flags = (is_fleecing ? BDRV_REQ_SERIALISING : 0) |
>> +        (compress ? BDRV_REQ_WRITE_COMPRESSED : 0);
> 
> Shouldn’t we keep the is_fleecing check in block_copy_state_new()? We must perform it at least once, but there is no benefit in repeating it on every block_copy_set_copy_opts() call, right?
> 

I think, it may help if user calls block_copy_set_copy_opts() after graph change


-- 
Best regards,
Vladimir


^ permalink raw reply	[flat|nested] 47+ messages in thread

* Re: [PATCH v7 17/33] block/copy-before-write: bdrv_cbw_append(): drop unused compress arg
  2021-08-10 15:17   ` Hanna Reitz
@ 2021-08-23 16:33     ` Vladimir Sementsov-Ogievskiy
  0 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-23 16:33 UTC (permalink / raw)
  To: Hanna Reitz, qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	jsnow, mreitz, kwolf

10.08.2021 18:17, Hanna Reitz wrote:
> On 04.08.21 11:37, Vladimir Sementsov-Ogievskiy wrote:
>> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
>> ---
>>   block/copy-before-write.h | 1 -
>>   block/backup.c            | 2 +-
>>   block/copy-before-write.c | 7 +++----
>>   3 files changed, 4 insertions(+), 6 deletions(-)
> 
> Well, I mean, it isn’t exactly syntactically unused before this patch; it’s only unused because this patch drops it from cbw_init(), too.
> 
> It definitely is functionally unused, though, so:
> 
> Reviewed-by: Hanna Reitz <hreitz@redhat.com>
> 
> I wonder whether we should drop @use_copy_range and @compress from block_copy_state_new(), too, though.
> 

Yes they are useless now.. I can add a patch.


-- 
Best regards,
Vladimir


^ permalink raw reply	[flat|nested] 47+ messages in thread

* Re: [PATCH v7 25/33] iotests.py: VM: add own __enter__ method
  2021-08-04 16:27   ` John Snow
@ 2021-08-23 17:22     ` Vladimir Sementsov-Ogievskiy
  0 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-23 17:22 UTC (permalink / raw)
  To: John Snow
  Cc: qemu-block, qemu-devel, Markus Armbruster, Eric Blake,
	Cleber Rosa, Eduardo Habkost, Daniel Berrange, Paolo Bonzini,
	Max Reitz, Kevin Wolf

04.08.2021 19:27, John Snow wrote:
> 
> On Wed, Aug 4, 2021 at 5:39 AM Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com <mailto:vsementsov@virtuozzo.com>> wrote:
> 
>     In superclass __enter__ method is defined with return value type hint
>     'QEMUMachine'. So, mypy thinks that return value of VM.__enter__ is
>     QEMUMachine. Let's redefine __enter__ in VM class, to give it correct
>     type hint.
> 
>     Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com <mailto:vsementsov@virtuozzo.com>>
>     Reviewed-by: Max Reitz <mreitz@redhat.com <mailto:mreitz@redhat.com>>
>     ---
>       tests/qemu-iotests/iotests.py | 4 ++++
>       1 file changed, 4 insertions(+)
> 
>     diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
>     index 89663dac06..025e288ddd 100644
>     --- a/tests/qemu-iotests/iotests.py
>     +++ b/tests/qemu-iotests/iotests.py
>     @@ -568,6 +568,10 @@ def remote_filename(path):
>       class VM(qtest.QEMUQtestMachine):
>           '''A QEMU VM'''
> 
>     +    # Redefine __enter__ with proper type hint
>     +    def __enter__(self) -> 'VM':
>     +        return self
>     +
>           def __init__(self, path_suffix=''):
>               name = "qemu%s-%d" % (path_suffix, os.getpid())
>               super().__init__(qemu_prog, qemu_opts, name=name,
>     -- 
>     2.29.2
> 
> 
> First and foremost:
> 
> Reviewed-by: John Snow <jsnow@redhat.com <mailto:jsnow@redhat.com>>
> Acked-by: John Snow <jsnow@redhat.com <mailto:jsnow@redhat.com>>
> 
> A more durable approach might be to annotate QEMUMachine differently such that subclasses get the right types automatically. See if this following snippet works instead of adding a new __enter__ method.
> 
> diff --git a/python/qemu/machine/machine.py b/python/qemu/machine/machine.py
> index 971ed7e8c6a..2e410103569 100644
> --- a/python/qemu/machine/machine.py
> +++ b/python/qemu/machine/machine.py
> @@ -36,6 +36,7 @@
>       Sequence,
>       Tuple,
>       Type,
> +    TypeVar,
>   )
> 
>   from qemu.qmp import (  # pylint: disable=import-error
> @@ -73,6 +74,9 @@ class AbnormalShutdown(QEMUMachineError):
>       """
> 
> 
> +_T = TypeVar('_T', bound='QEMUMachine')
> +
> +
>   class QEMUMachine:
>       """
>       A QEMU VM.
> @@ -166,7 +170,7 @@ def __init__(self,
>           self._remove_files: List[str] = []
>           self._user_killed = False
> 
> -    def __enter__(self) -> 'QEMUMachine':
> +    def __enter__(self: _T) -> _T:
>           return self
> 
>       def __exit__(self,
> @@ -182,8 +186,8 @@ def add_monitor_null(self) -> None:
>           self._args.append('-monitor')
>           self._args.append('null')
> 
> -    def add_fd(self, fd: int, fdset: int,
> -               opaque: str, opts: str = '') -> 'QEMUMachine':
> +    def add_fd(self: _T, fd: int, fdset: int,
> +               opaque: str, opts: str = '') -> _T:
>           """
>           Pass a file descriptor to the VM
>           """

That looks better, I'll go this way, thanks!

-- 
Best regards,
Vladimir


^ permalink raw reply	[flat|nested] 47+ messages in thread

* Re: [PATCH v7 07/33] block/block-copy: introduce block_copy_set_copy_opts()
  2021-08-23 12:05     ` Vladimir Sementsov-Ogievskiy
@ 2021-08-23 17:40       ` Vladimir Sementsov-Ogievskiy
  0 siblings, 0 replies; 47+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2021-08-23 17:40 UTC (permalink / raw)
  To: Hanna Reitz, qemu-block
  Cc: qemu-devel, armbru, eblake, crosa, ehabkost, berrange, pbonzini,
	jsnow, mreitz, kwolf

23.08.2021 15:05, Vladimir Sementsov-Ogievskiy wrote:
> 10.08.2021 17:55, Hanna Reitz wrote:
>> On 04.08.21 11:37, Vladimir Sementsov-Ogievskiy wrote:
>>> We'll need a possibility to set compress and use_copy_range options
>>> after initialization of the state. So make corresponding part of
>>> block_copy_state_new() separate and public.
>>>
>>> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
>>> ---
>>>   include/block/block-copy.h |  2 ++
>>>   block/block-copy.c         | 66 +++++++++++++++++++++-----------------
>>>   2 files changed, 39 insertions(+), 29 deletions(-)
>>>
>>> diff --git a/include/block/block-copy.h b/include/block/block-copy.h
>>> index 734389d32a..f0ba7bc828 100644
>>> --- a/include/block/block-copy.h
>>> +++ b/include/block/block-copy.h
>>> @@ -28,6 +28,8 @@ BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
>>>                                        int64_t cluster_size, bool use_copy_range,
>>>                                        bool compress, Error **errp);
>>> +void block_copy_set_copy_opts(BlockCopyState *s, bool use_copy_range,
>>> +                              bool compress);
>>>   void block_copy_set_progress_meter(BlockCopyState *s, ProgressMeter *pm);
>>>   void block_copy_state_free(BlockCopyState *s);
>>> diff --git a/block/block-copy.c b/block/block-copy.c
>>> index 58b4345a5a..84c29fb233 100644
>>> --- a/block/block-copy.c
>>> +++ b/block/block-copy.c
>>> @@ -315,21 +315,11 @@ static uint32_t block_copy_max_transfer(BdrvChild *source, BdrvChild *target)
>>>                                        target->bs->bl.max_transfer));
>>>   }
>>> -BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
>>> -                                     int64_t cluster_size, bool use_copy_range,
>>> -                                     bool compress, Error **errp)
>>> +/* Function should be called prior any actual copy request */
>>
>> Given this is something the caller should know, I’d prefer putting this into the block-copy.h header.
>>
>> However, I realize we have a wild mix of this in qemu and often do put such information into the C source file, so...
>>
>>> +void block_copy_set_copy_opts(BlockCopyState *s, bool use_copy_range,
>>> +                              bool compress)
>>>   {
>>> -    BlockCopyState *s;
>>> -    BdrvDirtyBitmap *copy_bitmap;
>>>       bool is_fleecing;
>>> -
>>> -    copy_bitmap = bdrv_create_dirty_bitmap(source->bs, cluster_size, NULL,
>>> -                                           errp);
>>> -    if (!copy_bitmap) {
>>> -        return NULL;
>>> -    }
>>> -    bdrv_disable_dirty_bitmap(copy_bitmap);
>>> -
>>>       /*
>>>        * 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
>>> @@ -344,24 +334,12 @@ BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
>>>        * For more information see commit f8d59dfb40bb and test
>>>        * tests/qemu-iotests/222
>>>        */
>>> -    is_fleecing = bdrv_chain_contains(target->bs, source->bs);
>>> +    is_fleecing = bdrv_chain_contains(s->target->bs, s->source->bs);
>>> -    s = g_new(BlockCopyState, 1);
>>> -    *s = (BlockCopyState) {
>>> -        .source = source,
>>> -        .target = target,
>>> -        .copy_bitmap = copy_bitmap,
>>> -        .cluster_size = cluster_size,
>>> -        .len = bdrv_dirty_bitmap_size(copy_bitmap),
>>> -        .write_flags = (is_fleecing ? BDRV_REQ_SERIALISING : 0) |
>>> -            (compress ? BDRV_REQ_WRITE_COMPRESSED : 0),
>>> -        .mem = shres_create(BLOCK_COPY_MAX_MEM),
>>> -        .max_transfer = QEMU_ALIGN_DOWN(
>>> -                                    block_copy_max_transfer(source, target),
>>> -                                    cluster_size),
>>> -    };
>>> +    s->write_flags = (is_fleecing ? BDRV_REQ_SERIALISING : 0) |
>>> +        (compress ? BDRV_REQ_WRITE_COMPRESSED : 0);
>>
>> Shouldn’t we keep the is_fleecing check in block_copy_state_new()? We must perform it at least once, but there is no benefit in repeating it on every block_copy_set_copy_opts() call, right?
>>
> 
> I think, it may help if user calls block_copy_set_copy_opts() after graph change
> 
> 

On the other hand, nobody actually call this function after generic graph change. And intended usage is start backup when source is already backing child of target.. Will change it, at least for code be more obvious and not raise questions.


-- 
Best regards,
Vladimir


^ permalink raw reply	[flat|nested] 47+ messages in thread

end of thread, other threads:[~2021-08-23 17:43 UTC | newest]

Thread overview: 47+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-08-04  9:37 [PATCH v7 00/33] block: publish backup-top filter Vladimir Sementsov-Ogievskiy
2021-08-04  9:37 ` [PATCH v7 01/33] block: introduce bdrv_replace_child_bs() Vladimir Sementsov-Ogievskiy
2021-08-04  9:37 ` [PATCH v7 02/33] block: introduce blk_replace_bs Vladimir Sementsov-Ogievskiy
2021-08-04  9:37 ` [PATCH v7 03/33] qdev-properties: PropertyInfo: add realized_set_allowed field Vladimir Sementsov-Ogievskiy
2021-08-04  9:37 ` [PATCH v7 04/33] qdev: allow setting drive property for realized device Vladimir Sementsov-Ogievskiy
2021-08-04  9:37 ` [PATCH v7 05/33] block: rename backup-top to copy-before-write Vladimir Sementsov-Ogievskiy
2021-08-04  9:37 ` [PATCH v7 06/33] block-copy: move detecting fleecing scheme to block-copy Vladimir Sementsov-Ogievskiy
2021-08-10 14:44   ` Hanna Reitz
2021-08-04  9:37 ` [PATCH v7 07/33] block/block-copy: introduce block_copy_set_copy_opts() Vladimir Sementsov-Ogievskiy
2021-08-10 14:55   ` Hanna Reitz
2021-08-23 12:05     ` Vladimir Sementsov-Ogievskiy
2021-08-23 17:40       ` Vladimir Sementsov-Ogievskiy
2021-08-04  9:37 ` [PATCH v7 08/33] block/backup: set copy_range and compress after filter insertion Vladimir Sementsov-Ogievskiy
2021-08-10 15:07   ` Hanna Reitz
2021-08-04  9:37 ` [PATCH v7 09/33] block/backup: move cluster size calculation to block-copy Vladimir Sementsov-Ogievskiy
2021-08-04  9:37 ` [PATCH v7 10/33] block/copy-before-write: relax permission requirements when no parents Vladimir Sementsov-Ogievskiy
2021-08-04  9:37 ` [PATCH v7 11/33] block/copy-before-write: drop extra bdrv_unref on failure path Vladimir Sementsov-Ogievskiy
2021-08-04  9:37 ` [PATCH v7 12/33] block/copy-before-write: use file child instead of backing Vladimir Sementsov-Ogievskiy
2021-08-04  9:37 ` [PATCH v7 13/33] block/copy-before-write: bdrv_cbw_append(): replace child at last Vladimir Sementsov-Ogievskiy
2021-08-04  9:37 ` [PATCH v7 14/33] block/copy-before-write: introduce cbw_init() Vladimir Sementsov-Ogievskiy
2021-08-04  9:37 ` [PATCH v7 15/33] block/copy-before-write: cbw_init(): rename variables Vladimir Sementsov-Ogievskiy
2021-08-04  9:37 ` [PATCH v7 16/33] block/copy-before-write: cbw_init(): use file child after attaching Vladimir Sementsov-Ogievskiy
2021-08-04  9:37 ` [PATCH v7 17/33] block/copy-before-write: bdrv_cbw_append(): drop unused compress arg Vladimir Sementsov-Ogievskiy
2021-08-10 15:17   ` Hanna Reitz
2021-08-23 16:33     ` Vladimir Sementsov-Ogievskiy
2021-08-04  9:37 ` [PATCH v7 18/33] block/copy-before-write: cbw_init(): use options Vladimir Sementsov-Ogievskiy
2021-08-10 15:18   ` Hanna Reitz
2021-08-04  9:37 ` [PATCH v7 19/33] block/copy-before-write: initialize block-copy bitmap Vladimir Sementsov-Ogievskiy
2021-08-04  9:38 ` [PATCH v7 20/33] block/block-copy: make setting progress optional Vladimir Sementsov-Ogievskiy
2021-08-10 15:23   ` Hanna Reitz
2021-08-04  9:38 ` [PATCH v7 21/33] block/copy-before-write: make public block driver Vladimir Sementsov-Ogievskiy
2021-08-04  9:38 ` [PATCH v7 22/33] qapi: publish copy-before-write filter Vladimir Sementsov-Ogievskiy
2021-08-04 13:18   ` Markus Armbruster
2021-08-04  9:38 ` [PATCH v7 23/33] python/qemu/machine.py: refactor _qemu_args() Vladimir Sementsov-Ogievskiy
2021-08-04  9:38 ` [PATCH v7 24/33] python/qemu/machine: QEMUMachine: improve qmp() method Vladimir Sementsov-Ogievskiy
2021-08-04  9:38 ` [PATCH v7 25/33] iotests.py: VM: add own __enter__ method Vladimir Sementsov-Ogievskiy
2021-08-04 16:27   ` John Snow
2021-08-23 17:22     ` Vladimir Sementsov-Ogievskiy
2021-08-04  9:38 ` [PATCH v7 26/33] iotests/222: fix pylint and mypy complains Vladimir Sementsov-Ogievskiy
2021-08-04  9:38 ` [PATCH v7 27/33] iotests/222: constantly use single quotes for strings Vladimir Sementsov-Ogievskiy
2021-08-04  9:38 ` [PATCH v7 28/33] iotests: move 222 to tests/image-fleecing Vladimir Sementsov-Ogievskiy
2021-08-04  9:38 ` [PATCH v7 29/33] iotests.py: hmp_qemu_io: support qdev Vladimir Sementsov-Ogievskiy
2021-08-04 16:17   ` John Snow
2021-08-04  9:38 ` [PATCH v7 30/33] iotests/image-fleecing: proper source device Vladimir Sementsov-Ogievskiy
2021-08-04  9:38 ` [PATCH v7 31/33] iotests/image-fleecing: rename tgt_node Vladimir Sementsov-Ogievskiy
2021-08-04  9:38 ` [PATCH v7 32/33] iotests/image-fleecing: prepare for adding new test-case Vladimir Sementsov-Ogievskiy
2021-08-04  9:38 ` [PATCH v7 33/33] iotests/image-fleecing: add test-case for copy-before-write filter Vladimir Sementsov-Ogievskiy

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