Signed-off-by: Alberto Garcia <berto@igalia.com>
---
 qapi/block-core.json       | 18 +++++----
 blockdev.c                 | 78 +++++++++++++++++++++++---------------
 tests/qemu-iotests/155     |  9 +++--
 tests/qemu-iotests/165     |  4 +-
 tests/qemu-iotests/245     | 27 +++++++------
 tests/qemu-iotests/248     |  2 +-
 tests/qemu-iotests/248.out |  2 +-
 tests/qemu-iotests/296     |  9 +++--
 tests/qemu-iotests/298     |  4 +-
 9 files changed, 92 insertions(+), 61 deletions(-)

diff --git a/qapi/block-core.json b/qapi/block-core.json
index 9f555d5c1d..9150f765da 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -4181,13 +4181,15 @@
 ##
 # @x-blockdev-reopen:
 #
-# Reopens a block device using the given set of options. Any option
-# not specified will be reset to its default value regardless of its
-# previous status. If an option cannot be changed or a particular
+# Reopens one or more block devices using the given set of options.
+# Any option not specified will be reset to its default value regardless
+# of its previous status. If an option cannot be changed or a particular
 # driver does not support reopening then the command will return an
-# error.
+# error. All devices in the list are reopened in one transaction, so
+# if one of them fails then the whole transaction is cancelled.
 #
-# The top-level @node-name option (from BlockdevOptions) must be
+# The command receives a list of block devices to reopen. For each one
+# of them, the top-level @node-name option (from BlockdevOptions) must be
 # specified and is used to select the block device to be reopened.
 # Other @node-name options must be either omitted or set to the
 # current name of the appropriate node. This command won't change any
@@ -4207,8 +4209,8 @@
 #
 #  4) NULL: the current child (if any) is detached.
 #
-# Options (1) and (2) are supported in all cases, but at the moment
-# only @backing allows replacing or detaching an existing child.
+# Options (1) and (2) are supported in all cases. Option (3) is
+# supported for @file and @backing, and option (4) for @backing only.
 #
 # Unlike with blockdev-add, the @backing option must always be present
 # unless the node being reopened does not have a backing file and its
@@ -4218,7 +4220,7 @@
 # Since: 4.0
 ##
 { 'command': 'x-blockdev-reopen',
-  'data': 'BlockdevOptions', 'boxed': true }
+  'data': { 'options': ['BlockdevOptions'] } }
 
 ##
 # @blockdev-del:
diff --git a/blockdev.c b/blockdev.c
index 825d40aa11..7019397b05 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -3580,46 +3580,64 @@ fail:
     visit_free(v);
 }
 
-void qmp_x_blockdev_reopen(BlockdevOptions *options, Error **errp)
+void qmp_x_blockdev_reopen(BlockdevOptionsList *reopen_list, Error **errp)
 {
-    BlockDriverState *bs;
-    AioContext *ctx;
-    QObject *obj;
-    Visitor *v = qobject_output_visitor_new(&obj);
-    BlockReopenQueue *queue;
-    QDict *qdict;
+    BlockReopenQueue *queue = NULL;
+    GSList *aio_ctxs = NULL;
+    GSList *visitors = NULL;
+    GSList *drained = NULL;
 
-    /* Check for the selected node name */
-    if (!options->has_node_name) {
-        error_setg(errp, "node-name not specified");
-        goto fail;
-    }
+    /* Add each one of the BDS that we want to reopen to the queue */
+    for (; reopen_list != NULL; reopen_list = reopen_list->next) {
+        BlockdevOptions *options = reopen_list->value;
+        BlockDriverState *bs;
+        AioContext *ctx;
+        QObject *obj;
+        Visitor *v;
+        QDict *qdict;
 
-    bs = bdrv_find_node(options->node_name);
-    if (!bs) {
-        error_setg(errp, "Failed to find node with node-name='%s'",
+        /* Check for the selected node name */
+        if (!options->has_node_name) {
+            error_setg(errp, "node-name not specified");
+            goto fail;
+        }
+
+        bs = bdrv_find_node(options->node_name);
+        if (!bs) {
+            error_setg(errp, "Failed to find node with node-name='%s'",
                    options->node_name);
-        goto fail;
+            goto fail;
+        }
+
+        v = qobject_output_visitor_new(&obj);
+        visitors = g_slist_prepend(visitors, v);
+
+        /* Put all options in a QDict and flatten it */
+        visit_type_BlockdevOptions(v, NULL, &options, &error_abort);
+        visit_complete(v, &obj);
+        qdict = qobject_to(QDict, obj);
+
+        qdict_flatten(qdict);
+
+        ctx = bdrv_get_aio_context(bs);
+        if (!g_slist_find(aio_ctxs, ctx)) {
+            aio_ctxs = g_slist_prepend(aio_ctxs, ctx);
+            aio_context_acquire(ctx);
+        }
+        bdrv_subtree_drained_begin(bs);
+        queue = bdrv_reopen_queue(queue, bs, qdict, false);
+        drained = g_slist_prepend(drained, bs);
     }
 
-    /* Put all options in a QDict and flatten it */
-    visit_type_BlockdevOptions(v, NULL, &options, &error_abort);
-    visit_complete(v, &obj);
-    qdict = qobject_to(QDict, obj);
-
-    qdict_flatten(qdict);
-
     /* Perform the reopen operation */
-    ctx = bdrv_get_aio_context(bs);
-    aio_context_acquire(ctx);
-    bdrv_subtree_drained_begin(bs);
-    queue = bdrv_reopen_queue(NULL, bs, qdict, false);
     bdrv_reopen_multiple(queue, errp);
-    bdrv_subtree_drained_end(bs);
-    aio_context_release(ctx);
+    queue = NULL;
 
 fail:
-    visit_free(v);
+    bdrv_reopen_queue_free(queue);
+    g_slist_free_full(drained, (GDestroyNotify) bdrv_subtree_drained_end);
+    g_slist_free_full(aio_ctxs, (GDestroyNotify) aio_context_release);
+    g_slist_free_full(visitors, (GDestroyNotify) visit_free);
 }
 
 void qmp_blockdev_del(const char *node_name, Error **errp)
diff --git a/tests/qemu-iotests/155 b/tests/qemu-iotests/155
index bafef9dd9a..3400b0312a 100755
--- a/tests/qemu-iotests/155
+++ b/tests/qemu-iotests/155
@@ -261,9 +261,12 @@ class TestBlockdevMirrorReopen(MirrorBaseClass):
             result = self.vm.qmp('blockdev-add', node_name="backing",
                                  driver="null-co")
             self.assert_qmp(result, 'return', {})
-            result = self.vm.qmp('x-blockdev-reopen', node_name="target",
-                                 driver=iotests.imgfmt, file="target-file",
-                                 backing="backing")
+            result = self.vm.qmp('x-blockdev-reopen', options = [{
+                                     'node-name': "target",
+                                     'driver': iotests.imgfmt,
+                                     'file': "target-file",
+                                     'backing': "backing"
+                                 }])
             self.assert_qmp(result, 'return', {})
 
 class TestBlockdevMirrorReopenIothread(TestBlockdevMirrorReopen):
diff --git a/tests/qemu-iotests/165 b/tests/qemu-iotests/165
index abc4ffadd5..57aa88ecae 100755
--- a/tests/qemu-iotests/165
+++ b/tests/qemu-iotests/165
@@ -137,7 +137,7 @@ class TestPersistentDirtyBitmap(iotests.QMPTestCase):
         assert sha256_1 == self.getSha256()
 
         # Reopen to RW
-        result = self.vm.qmp('x-blockdev-reopen', **{
+        result = self.vm.qmp('x-blockdev-reopen', options = [{
             'node-name': 'node0',
             'driver': iotests.imgfmt,
             'file': {
@@ -145,7 +145,7 @@ class TestPersistentDirtyBitmap(iotests.QMPTestCase):
                 'filename': disk
             },
             'read-only': False
-        })
+        }])
         self.assert_qmp(result, 'return', {})
 
         # Check that bitmap is reopened to RW and we can write to it.
diff --git a/tests/qemu-iotests/245 b/tests/qemu-iotests/245
index caebef4ac8..c27557fa6b 100755
--- a/tests/qemu-iotests/245
+++ b/tests/qemu-iotests/245
@@ -85,8 +85,18 @@ class TestBlockdevReopen(iotests.QMPTestCase):
                          "Expected output of %d qemu-io commands, found %d" %
                          (found, self.total_io_cmds))
 
-    # Run x-blockdev-reopen with 'opts' but applying 'newopts'
-    # on top of it. The original 'opts' dict is unmodified
+    # Run x-blockdev-reopen on a list of block devices
+    def reopenMultiple(self, opts, errmsg = None):
+        result = self.vm.qmp('x-blockdev-reopen', conv_keys = False, options = opts)
+        if errmsg:
+            self.assert_qmp(result, 'error/class', 'GenericError')
+            self.assert_qmp(result, 'error/desc', errmsg)
+        else:
+            self.assert_qmp(result, 'return', {})
+
+    # Run x-blockdev-reopen on a single block device (specified by
+    # 'opts') but applying 'newopts' on top of it. The original 'opts'
+    # dict is unmodified
     def reopen(self, opts, newopts = {}, errmsg = None):
         opts = copy.deepcopy(opts)
 
@@ -101,12 +111,7 @@ class TestBlockdevReopen(iotests.QMPTestCase):
                 subdict = opts[prefix]
             subdict[key] = value
 
-        result = self.vm.qmp('x-blockdev-reopen', conv_keys = False, **opts)
-        if errmsg:
-            self.assert_qmp(result, 'error/class', 'GenericError')
-            self.assert_qmp(result, 'error/desc', errmsg)
-        else:
-            self.assert_qmp(result, 'return', {})
+        self.reopenMultiple([ opts ], errmsg)
 
 
     # Run query-named-block-nodes and return the specified entry
@@ -142,10 +147,10 @@ class TestBlockdevReopen(iotests.QMPTestCase):
         # We cannot change any of these
         self.reopen(opts, {'node-name': 'not-found'}, "Failed to find node with node-name='not-found'")
         self.reopen(opts, {'node-name': ''}, "Failed to find node with node-name=''")
-        self.reopen(opts, {'node-name': None}, "Invalid parameter type for 'node-name', expected: string")
+        self.reopen(opts, {'node-name': None}, "Invalid parameter type for 'options[0].node-name', expected: string")
         self.reopen(opts, {'driver': 'raw'}, "Cannot change the option 'driver'")
         self.reopen(opts, {'driver': ''}, "Invalid parameter ''")
-        self.reopen(opts, {'driver': None}, "Invalid parameter type for 'driver', expected: string")
+        self.reopen(opts, {'driver': None}, "Invalid parameter type for 'options[0].driver', expected: string")
         self.reopen(opts, {'file': 'not-found'}, "Cannot find device='' nor node-name='not-found'")
         self.reopen(opts, {'file': ''}, "Cannot find device='' nor node-name=''")
         self.reopen(opts, {'file': None}, "Invalid parameter type for 'file', expected: BlockdevRef")
@@ -154,7 +159,7 @@ class TestBlockdevReopen(iotests.QMPTestCase):
         self.reopen(opts, {'file.filename': hd_path[1]}, "Cannot change the option 'filename'")
         self.reopen(opts, {'file.aio': 'native'}, "Cannot change the option 'aio'")
         self.reopen(opts, {'file.locking': 'off'}, "Cannot change the option 'locking'")
-        self.reopen(opts, {'file.filename': None}, "Invalid parameter type for 'file.filename', expected: string")
+        self.reopen(opts, {'file.filename': None}, "Invalid parameter type for 'options[0].file.filename', expected: string")
 
         # node-name is optional in BlockdevOptions, but x-blockdev-reopen needs it
         del opts['node-name']
diff --git a/tests/qemu-iotests/248 b/tests/qemu-iotests/248
index 4daaed1530..03911333c4 100755
--- a/tests/qemu-iotests/248
+++ b/tests/qemu-iotests/248
@@ -63,7 +63,7 @@ vm.get_qmp_events()
 
 del blockdev_opts['file']['size']
 vm.qmp_log('x-blockdev-reopen', filters=[filter_qmp_testfiles],
-           **blockdev_opts)
+           options = [ blockdev_opts ])
 
 vm.qmp_log('block-job-resume', device='drive0')
 vm.event_wait('JOB_STATUS_CHANGE', timeout=1.0,
diff --git a/tests/qemu-iotests/248.out b/tests/qemu-iotests/248.out
index 369b25bf26..893f625347 100644
--- a/tests/qemu-iotests/248.out
+++ b/tests/qemu-iotests/248.out
@@ -2,7 +2,7 @@
 {"return": {}}
 {"execute": "blockdev-mirror", "arguments": {"device": "drive0", "on-target-error": "enospc", "sync": "full", "target": "target"}}
 {"return": {}}
-{"execute": "x-blockdev-reopen", "arguments": {"driver": "qcow2", "file": {"driver": "raw", "file": {"driver": "file", "filename": "TEST_DIR/PID-target"}}, "node-name": "target"}}
+{"execute": "x-blockdev-reopen", "arguments": {"options": [{"driver": "qcow2", "file": {"driver": "raw", "file": {"driver": "file", "filename": "TEST_DIR/PID-target"}}, "node-name": "target"}]}}
 {"return": {}}
 {"execute": "block-job-resume", "arguments": {"device": "drive0"}}
 {"return": {}}
diff --git a/tests/qemu-iotests/296 b/tests/qemu-iotests/296
index 7c65e987a1..74b74511b6 100755
--- a/tests/qemu-iotests/296
+++ b/tests/qemu-iotests/296
@@ -120,8 +120,7 @@ class EncryptionSetupTestCase(iotests.QMPTestCase):
 
         command = 'x-blockdev-reopen' if reOpen else 'blockdev-add'
 
-        result = vm.qmp(command, **
-            {
+        opts = {
                 'driver': iotests.imgfmt,
                 'node-name': id,
                 'read-only': readOnly,
@@ -131,7 +130,11 @@ class EncryptionSetupTestCase(iotests.QMPTestCase):
                     'filename': test_img,
                 }
             }
-        )
+
+        if reOpen:
+            result = vm.qmp(command, options = [ opts ])
+        else:
+            result = vm.qmp(command, **opts)
         self.assert_qmp(result, 'return', {})
 
 
diff --git a/tests/qemu-iotests/298 b/tests/qemu-iotests/298
index d535946b5f..4efdb35b91 100755
--- a/tests/qemu-iotests/298
+++ b/tests/qemu-iotests/298
@@ -98,7 +98,7 @@ class TestPreallocateFilter(TestPreallocateBase):
         self.check_big()
 
     def test_reopen_opts(self):
-        result = self.vm.qmp('x-blockdev-reopen', **{
+        result = self.vm.qmp('x-blockdev-reopen', options = [{
             'node-name': 'disk',
             'driver': iotests.imgfmt,
             'file': {
@@ -112,7 +112,7 @@ class TestPreallocateFilter(TestPreallocateBase):
                     'filename': disk
                 }
             }
-        })
+        }])
         self.assert_qmp(result, 'return', {})
 
         self.vm.hmp_qemu_io('drive0', 'write 0 1M')
-- 
2.20.1

17.03.2021 20:15, Alberto Garcia wrote:
> Signed-off-by: Alberto Garcia <berto@igalia.com>
> ---
>   qapi/block-core.json       | 18 +++++----
>   blockdev.c                 | 78 +++++++++++++++++++++++---------------
>   tests/qemu-iotests/155     |  9 +++--
>   tests/qemu-iotests/165     |  4 +-
>   tests/qemu-iotests/245     | 27 +++++++------
>   tests/qemu-iotests/248     |  2 +-
>   tests/qemu-iotests/248.out |  2 +-
>   tests/qemu-iotests/296     |  9 +++--
>   tests/qemu-iotests/298     |  4 +-
>   9 files changed, 92 insertions(+), 61 deletions(-)
> 
> diff --git a/qapi/block-core.json b/qapi/block-core.json
> index 9f555d5c1d..9150f765da 100644
> --- a/qapi/block-core.json
> +++ b/qapi/block-core.json
> @@ -4181,13 +4181,15 @@
>   ##
>   # @x-blockdev-reopen:
>   #
> -# Reopens a block device using the given set of options. Any option
> -# not specified will be reset to its default value regardless of its
> -# previous status. If an option cannot be changed or a particular
> +# Reopens one or more block devices using the given set of options.
> +# Any option not specified will be reset to its default value regardless
> +# of its previous status. If an option cannot be changed or a particular
>   # driver does not support reopening then the command will return an
> -# error.
> +# error. All devices in the list are reopened in one transaction, so
> +# if one of them fails then the whole transaction is cancelled.
>   #
> -# The top-level @node-name option (from BlockdevOptions) must be
> +# The command receives a list of block devices to reopen. For each one
> +# of them, the top-level @node-name option (from BlockdevOptions) must be
>   # specified and is used to select the block device to be reopened.
>   # Other @node-name options must be either omitted or set to the
>   # current name of the appropriate node. This command won't change any
> @@ -4207,8 +4209,8 @@
>   #
>   #  4) NULL: the current child (if any) is detached.
>   #
> -# Options (1) and (2) are supported in all cases, but at the moment
> -# only @backing allows replacing or detaching an existing child.
> +# Options (1) and (2) are supported in all cases. Option (3) is
> +# supported for @file and @backing, and option (4) for @backing only.

A bit of it should be already updated in "[PATCH v4 2/6] block: Allow changing bs->file on reopen"

>   #
>   # Unlike with blockdev-add, the @backing option must always be present
>   # unless the node being reopened does not have a backing file and its
> @@ -4218,7 +4220,7 @@
>   # Since: 4.0
>   ##
>   { 'command': 'x-blockdev-reopen',
> -  'data': 'BlockdevOptions', 'boxed': true }
> +  'data': { 'options': ['BlockdevOptions'] } }
>   
>   ##
>   # @blockdev-del:
> diff --git a/blockdev.c b/blockdev.c
> index 825d40aa11..7019397b05 100644
> --- a/blockdev.c
> +++ b/blockdev.c
> @@ -3580,46 +3580,64 @@ fail:
>       visit_free(v);
>   }
>   
> -void qmp_x_blockdev_reopen(BlockdevOptions *options, Error **errp)
> +void qmp_x_blockdev_reopen(BlockdevOptionsList *reopen_list, Error **errp)
>   {
> -    BlockDriverState *bs;
> -    AioContext *ctx;
> -    QObject *obj;
> -    Visitor *v = qobject_output_visitor_new(&obj);
> -    BlockReopenQueue *queue;
> -    QDict *qdict;
> +    BlockReopenQueue *queue = NULL;
> +    GSList *aio_ctxs = NULL;
> +    GSList *visitors = NULL;
> +    GSList *drained = NULL;
>   
> -    /* Check for the selected node name */
> -    if (!options->has_node_name) {
> -        error_setg(errp, "node-name not specified");
> -        goto fail;
> -    }
> +    /* Add each one of the BDS that we want to reopen to the queue */
> +    for (; reopen_list != NULL; reopen_list = reopen_list->next) {
> +        BlockdevOptions *options = reopen_list->value;
> +        BlockDriverState *bs;
> +        AioContext *ctx;
> +        QObject *obj;
> +        Visitor *v;
> +        QDict *qdict;
>   
> -    bs = bdrv_find_node(options->node_name);
> -    if (!bs) {
> -        error_setg(errp, "Failed to find node with node-name='%s'",
> +        /* Check for the selected node name */
> +        if (!options->has_node_name) {
> +            error_setg(errp, "node-name not specified");
> +            goto fail;
> +        }
> +
> +        bs = bdrv_find_node(options->node_name);
> +        if (!bs) {
> +            error_setg(errp, "Failed to find node with node-name='%s'",
>                      options->node_name);
> -        goto fail;
> +            goto fail;
> +        }
> +
> +        v = qobject_output_visitor_new(&obj);
> +        visitors = g_slist_prepend(visitors, v);

I'd better just call visit_free inside the block instead of putting v to list be freed later after the block..

> +
> +        /* Put all options in a QDict and flatten it */
> +        visit_type_BlockdevOptions(v, NULL, &options, &error_abort);
> +        visit_complete(v, &obj);
> +        qdict = qobject_to(QDict, obj);
> +
> +        qdict_flatten(qdict);
> +
> +        ctx = bdrv_get_aio_context(bs);
> +        if (!g_slist_find(aio_ctxs, ctx)) {
> +            aio_ctxs = g_slist_prepend(aio_ctxs, ctx);
> +            aio_context_acquire(ctx);
> +        }
> +        bdrv_subtree_drained_begin(bs);

I expect Kevin will complain that aquiring several context and drain them all is a bad idea as it leads to deadlocks..
For more information look at the branches
   [PATCH v2 29/36] blockdev: qmp_x_blockdev_reopen: acquire all contexts
amd
   [PATCH v2 30/36] block: bdrv_reopen_multiple: refresh permissions on updated graph

So, probably here we should acquire context in a loop to call bdrv_reopen_queue() (which I think shoud not require drained section).

And then, bdrv_reopen_multiple() is called with no aio context acquired, and no drained section.. And it shoud be refactored to properly operate with acquiring and realeasing the contexts and drained sections when needed...

(note preexisting problem of reopen, that during reopen the whole tree may be moved to another aio context, but we continue operations with acquired old aio context which is wrong).


> +        queue = bdrv_reopen_queue(queue, bs, qdict, false);
> +        drained = g_slist_prepend(drained, bs);
>       }
>   
> -    /* Put all options in a QDict and flatten it */
> -    visit_type_BlockdevOptions(v, NULL, &options, &error_abort);
> -    visit_complete(v, &obj);
> -    qdict = qobject_to(QDict, obj);
> -
> -    qdict_flatten(qdict);
> -
>       /* Perform the reopen operation */
> -    ctx = bdrv_get_aio_context(bs);
> -    aio_context_acquire(ctx);
> -    bdrv_subtree_drained_begin(bs);
> -    queue = bdrv_reopen_queue(NULL, bs, qdict, false);
>       bdrv_reopen_multiple(queue, errp);
> -    bdrv_subtree_drained_end(bs);
> -    aio_context_release(ctx);
> +    queue = NULL;
>   
>   fail:
> -    visit_free(v);
> +    bdrv_reopen_queue_free(queue);
> +    g_slist_free_full(drained, (GDestroyNotify) bdrv_subtree_drained_end);
> +    g_slist_free_full(aio_ctxs, (GDestroyNotify) aio_context_release);
> +    g_slist_free_full(visitors, (GDestroyNotify) visit_free);
>   }
>   


-- 
Best regards,
Vladimir