/*
- * Copyright (C) 2016-2021 Red Hat, Inc.
+ * Copyright (C) 2016-2022 Red Hat, Inc.
* Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws>
*
* Network Block Device Server Side
int64_t size;
uint64_t perm, shared_perm;
bool readonly = !exp_args->writable;
- bool shared = !exp_args->writable;
BlockDirtyBitmapOrStrList *bitmaps;
size_t i;
int ret;
exp->description = g_strdup(arg->description);
exp->nbdflags = (NBD_FLAG_HAS_FLAGS | NBD_FLAG_SEND_FLUSH |
NBD_FLAG_SEND_FUA | NBD_FLAG_SEND_CACHE);
+
+ if (nbd_server_max_connections() != 1) {
+ exp->nbdflags |= NBD_FLAG_CAN_MULTI_CONN;
+ }
if (readonly) {
exp->nbdflags |= NBD_FLAG_READ_ONLY;
- if (shared) {
- exp->nbdflags |= NBD_FLAG_CAN_MULTI_CONN;
- }
} else {
exp->nbdflags |= (NBD_FLAG_SEND_TRIM | NBD_FLAG_SEND_WRITE_ZEROES |
NBD_FLAG_SEND_FAST_ZERO);
# recreated on the fly while the NBD server is active.
# If missing, it will default to denying access (since 4.0).
# @max-connections: The maximum number of connections to allow at the same
-# time, 0 for unlimited. (since 5.2; default: 0)
+# time, 0 for unlimited. Setting this to 1 also stops
+# the server from advertising multiple client support
+# (since 5.2; default: 0)
#
# Since: 4.2
##
# recreated on the fly while the NBD server is active.
# If missing, it will default to denying access (since 4.0).
# @max-connections: The maximum number of connections to allow at the same
-# time, 0 for unlimited. (since 5.2; default: 0)
+# time, 0 for unlimited. Setting this to 1 also stops
+# the server from advertising multiple client support
+# (since 5.2; default: 0).
#
# Returns: error if the server is already running.
#
--- /dev/null
+#!/usr/bin/env python3
+# group: rw auto quick
+#
+# Test cases for NBD multi-conn advertisement
+#
+# Copyright (C) 2022 Red Hat, Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+import os
+from contextlib import contextmanager
+import iotests
+from iotests import qemu_img_create, qemu_io
+
+
+disk = os.path.join(iotests.test_dir, 'disk')
+size = '4M'
+nbd_sock = os.path.join(iotests.sock_dir, 'nbd_sock')
+nbd_uri = 'nbd+unix:///{}?socket=' + nbd_sock
+
+
+@contextmanager
+def open_nbd(export_name):
+ h = nbd.NBD()
+ try:
+ h.connect_uri(nbd_uri.format(export_name))
+ yield h
+ finally:
+ h.shutdown()
+
+class TestNbdMulticonn(iotests.QMPTestCase):
+ def setUp(self):
+ qemu_img_create('-f', iotests.imgfmt, disk, size)
+ qemu_io('-c', 'w -P 1 0 2M', '-c', 'w -P 2 2M 2M', disk)
+
+ self.vm = iotests.VM()
+ self.vm.launch()
+ result = self.vm.qmp('blockdev-add', {
+ 'driver': 'qcow2',
+ 'node-name': 'n',
+ 'file': {'driver': 'file', 'filename': disk}
+ })
+ self.assert_qmp(result, 'return', {})
+
+ def tearDown(self):
+ self.vm.shutdown()
+ os.remove(disk)
+ try:
+ os.remove(nbd_sock)
+ except OSError:
+ pass
+
+ @contextmanager
+ def run_server(self, max_connections=None):
+ args = {
+ 'addr': {
+ 'type': 'unix',
+ 'data': {'path': nbd_sock}
+ }
+ }
+ if max_connections is not None:
+ args['max-connections'] = max_connections
+
+ result = self.vm.qmp('nbd-server-start', args)
+ self.assert_qmp(result, 'return', {})
+ yield
+
+ result = self.vm.qmp('nbd-server-stop')
+ self.assert_qmp(result, 'return', {})
+
+ def add_export(self, name, writable=None):
+ args = {
+ 'type': 'nbd',
+ 'id': name,
+ 'node-name': 'n',
+ 'name': name,
+ }
+ if writable is not None:
+ args['writable'] = writable
+
+ result = self.vm.qmp('block-export-add', args)
+ self.assert_qmp(result, 'return', {})
+
+ def test_default_settings(self):
+ with self.run_server():
+ self.add_export('r')
+ self.add_export('w', writable=True)
+ with open_nbd('r') as h:
+ self.assertTrue(h.can_multi_conn())
+ with open_nbd('w') as h:
+ self.assertTrue(h.can_multi_conn())
+
+ def test_limited_connections(self):
+ with self.run_server(max_connections=1):
+ self.add_export('r')
+ self.add_export('w', writable=True)
+ with open_nbd('r') as h:
+ self.assertFalse(h.can_multi_conn())
+ with open_nbd('w') as h:
+ self.assertFalse(h.can_multi_conn())
+
+ def test_parallel_writes(self):
+ with self.run_server():
+ self.add_export('w', writable=True)
+
+ clients = [nbd.NBD() for _ in range(3)]
+ for c in clients:
+ c.connect_uri(nbd_uri.format('w'))
+ self.assertTrue(c.can_multi_conn())
+
+ initial_data = clients[0].pread(1024 * 1024, 0)
+ self.assertEqual(initial_data, b'\x01' * 1024 * 1024)
+
+ updated_data = b'\x03' * 1024 * 1024
+ clients[1].pwrite(updated_data, 0)
+ clients[2].flush()
+ current_data = clients[0].pread(1024 * 1024, 0)
+
+ self.assertEqual(updated_data, current_data)
+
+ for i in range(3):
+ clients[i].shutdown()
+
+
+if __name__ == '__main__':
+ try:
+ # Easier to use libnbd than to try and set up parallel
+ # 'qemu-nbd --list' or 'qemu-io' processes, but not all systems
+ # have libnbd installed.
+ import nbd # type: ignore
+
+ iotests.main(supported_fmts=['qcow2'])
+ except ImportError:
+ iotests.notrun('libnbd not installed')
projects / thirdparty / qemu.git / commitdiff
