[RFC PATCH v2 4/4] iotests: Test reopening multiple devices at the same time

[Alberto Garcia <berto@igalia.com>]

Signed-off-by: Alberto Garcia <berto@igalia.com>
---
 tests/qemu-iotests/245     | 40 ++++++++++++++++++++++++++++++++++++++
 tests/qemu-iotests/245.out |  4 ++--
 2 files changed, 42 insertions(+), 2 deletions(-)

diff --git a/tests/qemu-iotests/245 b/tests/qemu-iotests/245
index 850c9f070b..d18dbbe638 100755
--- a/tests/qemu-iotests/245
+++ b/tests/qemu-iotests/245
@@ -574,6 +574,46 @@ class TestBlockdevReopen(iotests.QMPTestCase):
         self.reopen(opts, {'file': 'hd1-file'})
         self.run_qemu_io("hd", "read  -P 0xa1 0 10k")
 
+    def test_swap_files(self):
+        opts0 = hd_opts(0)
+        opts2 = hd_opts(2)
+
+        # Add hd0 and hd2 (none of them with backing files)
+        result = self.vm.qmp('blockdev-add', conv_keys = False, **opts0)
+        self.assert_qmp(result, 'return', {})
+        result = self.vm.qmp('blockdev-add', conv_keys = False, **opts2)
+        self.assert_qmp(result, 'return', {})
+
+        # Write different data to both block devices
+        self.run_qemu_io("hd0", "write -P 0xa0 0 1k")
+        self.run_qemu_io("hd2", "write -P 0xa2 0 1k")
+
+        # Check that the data reads correctly
+        self.run_qemu_io("hd0", "read  -P 0xa0 0 1k")
+        self.run_qemu_io("hd2", "read  -P 0xa2 0 1k")
+
+        # It's not possible to make a block device use an image that
+        # is already being used by the other device.
+        self.reopen(opts0, {'file': 'hd2-file'},
+                    "Conflicts with use by hd0 as 'file', which does not allow 'write, resize' on hd2-file")
+        self.reopen(opts2, {'file': 'hd0-file'},
+                    "Conflicts with use by hd2 as 'file', which does not allow 'write, resize' on hd0-file")
+
+        # But we can swap the images if we reopen both devices at the
+        # same time
+        opts0['file'] = 'hd2-file'
+        opts2['file'] = 'hd0-file'
+        self.reopenMultiple([opts0, opts2])
+        self.run_qemu_io("hd0", "read  -P 0xa2 0 1k")
+        self.run_qemu_io("hd2", "read  -P 0xa0 0 1k")
+
+        # And we can of course come back to the original state
+        opts0['file'] = 'hd0-file'
+        opts2['file'] = 'hd2-file'
+        self.reopenMultiple([opts0, opts2])
+        self.run_qemu_io("hd0", "read  -P 0xa0 0 1k")
+        self.run_qemu_io("hd2", "read  -P 0xa2 0 1k")
+
     def test_insert_throttle_filter(self):
         hd0_opts = hd_opts(0)
         result = self.vm.qmp('blockdev-add', conv_keys = False, **hd0_opts)
diff --git a/tests/qemu-iotests/245.out b/tests/qemu-iotests/245.out
index 537a2b5b63..1f9debbd61 100644
--- a/tests/qemu-iotests/245.out
+++ b/tests/qemu-iotests/245.out
@@ -10,8 +10,8 @@
 {"return": {}}
 {"data": {"id": "stream0", "type": "stream"}, "event": "BLOCK_JOB_PENDING", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 {"data": {"device": "stream0", "len": 3145728, "offset": 3145728, "speed": 0, "type": "stream"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
-.......................
+........................
 ----------------------------------------------------------------------
-Ran 23 tests
+Ran 24 tests
 
 OK
-- 
2.20.1