* [PATCH 1/2] iotests: Refactor blockdev-reopen test for iothreads
2020-02-27 18:18 [PATCH 0/2] block: bdrv_reopen() with backing file in different AioContext Kevin Wolf
@ 2020-02-27 18:18 ` Kevin Wolf
2020-02-27 18:18 ` [PATCH 2/2] block: bdrv_reopen() with backing file in different AioContext Kevin Wolf
2020-03-04 9:29 ` [PATCH 0/2] " Peter Krempa
2 siblings, 0 replies; 7+ messages in thread
From: Kevin Wolf @ 2020-02-27 18:18 UTC (permalink / raw)
To: qemu-block; +Cc: kwolf, pkrempa, berto, qemu-devel, mreitz
We'll want to test more than one successful case in the future, so
prepare the test for that by a refactoring that runs each scenario in a
separate VM.
test_iothreads_switch_{backing,overlay} currently produce errors, but
these are cases that should actually work, by switching either the
backing file node or the overlay node to the AioContext of the other
node.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
tests/qemu-iotests/245 | 42 +++++++++++++++++++++++++++++---------
tests/qemu-iotests/245.out | 4 ++--
2 files changed, 34 insertions(+), 12 deletions(-)
diff --git a/tests/qemu-iotests/245 b/tests/qemu-iotests/245
index 489bf78bd0..5a2cd5ed0e 100755
--- a/tests/qemu-iotests/245
+++ b/tests/qemu-iotests/245
@@ -970,8 +970,7 @@ class TestBlockdevReopen(iotests.QMPTestCase):
self.assertEqual(self.get_node('hd1'), None)
self.assert_qmp(self.get_node('hd2'), 'ro', True)
- # We don't allow setting a backing file that uses a different AioContext
- def test_iothreads(self):
+ def run_test_iothreads(self, iothread_a, iothread_b, errmsg = None):
opts = hd_opts(0)
result = self.vm.qmp('blockdev-add', conv_keys = False, **opts)
self.assert_qmp(result, 'return', {})
@@ -986,20 +985,43 @@ class TestBlockdevReopen(iotests.QMPTestCase):
result = self.vm.qmp('object-add', qom_type='iothread', id='iothread1')
self.assert_qmp(result, 'return', {})
- result = self.vm.qmp('x-blockdev-set-iothread', node_name='hd0', iothread='iothread0')
+ result = self.vm.qmp('device_add', driver='virtio-scsi', id='scsi0',
+ iothread=iothread_a)
self.assert_qmp(result, 'return', {})
- self.reopen(opts, {'backing': 'hd2'}, "Cannot use a new backing file with a different AioContext")
-
- result = self.vm.qmp('x-blockdev-set-iothread', node_name='hd2', iothread='iothread1')
+ result = self.vm.qmp('device_add', driver='virtio-scsi', id='scsi1',
+ iothread=iothread_b)
self.assert_qmp(result, 'return', {})
- self.reopen(opts, {'backing': 'hd2'}, "Cannot use a new backing file with a different AioContext")
+ if iothread_a:
+ result = self.vm.qmp('device_add', driver='scsi-hd', drive='hd0',
+ share_rw=True, bus="scsi0.0")
+ self.assert_qmp(result, 'return', {})
- result = self.vm.qmp('x-blockdev-set-iothread', node_name='hd2', iothread='iothread0')
- self.assert_qmp(result, 'return', {})
+ if iothread_b:
+ result = self.vm.qmp('device_add', driver='scsi-hd', drive='hd2',
+ share_rw=True, bus="scsi1.0")
+ self.assert_qmp(result, 'return', {})
- self.reopen(opts, {'backing': 'hd2'})
+ self.reopen(opts, {'backing': 'hd2'}, errmsg)
+ self.vm.shutdown()
+
+ # We don't allow setting a backing file that uses a different AioContext if
+ # neither of them can switch to the other AioContext
+ def test_iothreads_error(self):
+ self.run_test_iothreads('iothread0', 'iothread1',
+ "Cannot use a new backing file with a different AioContext")
+
+ def test_iothreads_compatible_users(self):
+ self.run_test_iothreads('iothread0', 'iothread0')
+
+ def test_iothreads_switch_backing(self):
+ self.run_test_iothreads('iothread0', None,
+ "Cannot use a new backing file with a different AioContext")
+
+ def test_iothreads_switch_overlay(self):
+ self.run_test_iothreads(None, 'iothread0',
+ "Cannot use a new backing file with a different AioContext")
if __name__ == '__main__':
iotests.main(supported_fmts=["qcow2"],
diff --git a/tests/qemu-iotests/245.out b/tests/qemu-iotests/245.out
index a19de5214d..682b93394d 100644
--- a/tests/qemu-iotests/245.out
+++ b/tests/qemu-iotests/245.out
@@ -1,6 +1,6 @@
-..................
+.....................
----------------------------------------------------------------------
-Ran 18 tests
+Ran 21 tests
OK
{"execute": "job-finalize", "arguments": {"id": "commit0"}}
--
2.20.1
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PATCH 2/2] block: bdrv_reopen() with backing file in different AioContext
2020-02-27 18:18 [PATCH 0/2] block: bdrv_reopen() with backing file in different AioContext Kevin Wolf
2020-02-27 18:18 ` [PATCH 1/2] iotests: Refactor blockdev-reopen test for iothreads Kevin Wolf
@ 2020-02-27 18:18 ` Kevin Wolf
2020-03-05 15:54 ` Alberto Garcia
2020-03-04 9:29 ` [PATCH 0/2] " Peter Krempa
2 siblings, 1 reply; 7+ messages in thread
From: Kevin Wolf @ 2020-02-27 18:18 UTC (permalink / raw)
To: qemu-block; +Cc: kwolf, pkrempa, berto, qemu-devel, mreitz
This patch allows bdrv_reopen() (and therefore the x-blockdev-reopen QMP
command) to attach a node as the new backing file even if the node is in
a different AioContext than the parent if one of both nodes can be moved
to the AioContext of the other node.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
block.c | 36 +++++++++++++++++++++++++++---------
tests/qemu-iotests/245 | 8 +++-----
2 files changed, 30 insertions(+), 14 deletions(-)
diff --git a/block.c b/block.c
index 202c67e1e8..5dbba6cf31 100644
--- a/block.c
+++ b/block.c
@@ -3781,6 +3781,29 @@ static void bdrv_reopen_perm(BlockReopenQueue *q, BlockDriverState *bs,
*shared = cumulative_shared_perms;
}
+static bool bdrv_reopen_can_attach(BdrvChild *child,
+ BlockDriverState *new_child,
+ BlockDriverState *parent,
+ Error **errp)
+{
+ AioContext *parent_ctx = bdrv_get_aio_context(parent);
+ AioContext *child_ctx = bdrv_get_aio_context(new_child);
+ GSList *ignore;
+ bool ret;
+
+ ignore = g_slist_prepend(NULL, child);
+ ret = bdrv_can_set_aio_context(new_child, parent_ctx, &ignore, NULL);
+ g_slist_free(ignore);
+ if (ret) {
+ return ret;
+ }
+
+ ignore = g_slist_prepend(NULL, child);
+ ret = bdrv_can_set_aio_context(parent, child_ctx, &ignore, errp);
+ g_slist_free(ignore);
+ return ret;
+}
+
/*
* Take a BDRVReopenState and check if the value of 'backing' in the
* reopen_state->options QDict is valid or not.
@@ -3832,16 +3855,11 @@ static int bdrv_reopen_parse_backing(BDRVReopenState *reopen_state,
}
/*
- * TODO: before removing the x- prefix from x-blockdev-reopen we
- * should move the new backing file into the right AioContext
- * instead of returning an error.
+ * Check AioContext compatibility so that the bdrv_set_backing_hd() call in
+ * bdrv_reopen_commit() won't fail.
*/
- if (new_backing_bs) {
- if (bdrv_get_aio_context(new_backing_bs) != bdrv_get_aio_context(bs)) {
- error_setg(errp, "Cannot use a new backing file "
- "with a different AioContext");
- return -EINVAL;
- }
+ if (!bdrv_reopen_can_attach(bs->backing, bs, new_backing_bs, errp)) {
+ return -EINVAL;
}
/*
diff --git a/tests/qemu-iotests/245 b/tests/qemu-iotests/245
index 5a2cd5ed0e..d6135ec14d 100755
--- a/tests/qemu-iotests/245
+++ b/tests/qemu-iotests/245
@@ -1010,18 +1010,16 @@ class TestBlockdevReopen(iotests.QMPTestCase):
# neither of them can switch to the other AioContext
def test_iothreads_error(self):
self.run_test_iothreads('iothread0', 'iothread1',
- "Cannot use a new backing file with a different AioContext")
+ "Cannot change iothread of active block backend")
def test_iothreads_compatible_users(self):
self.run_test_iothreads('iothread0', 'iothread0')
def test_iothreads_switch_backing(self):
- self.run_test_iothreads('iothread0', None,
- "Cannot use a new backing file with a different AioContext")
+ self.run_test_iothreads('iothread0', None)
def test_iothreads_switch_overlay(self):
- self.run_test_iothreads(None, 'iothread0',
- "Cannot use a new backing file with a different AioContext")
+ self.run_test_iothreads(None, 'iothread0')
if __name__ == '__main__':
iotests.main(supported_fmts=["qcow2"],
--
2.20.1
^ permalink raw reply related [flat|nested] 7+ messages in thread