Merge remote-tracking branch 'remotes/bonzini-gitlab/tags/for-upstream' into staging

* qtest documentation improvements (Eduardo, myself)
* libqtest event buffering (Maxim)
* use RCU for list of children of a bus (Maxim)
* move more files to softmmu/ (myself)
* meson.build cleanups, qemu-storage-daemon fix (Philippe)

# gpg: Signature made Mon 12 Oct 2020 16:55:19 BST
# gpg:                using RSA key F13338574B662389866C7682BFFBD25F78C7AE83
# gpg:                issuer "pbonzini@redhat.com"
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>" [full]
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>" [full]
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4  E2F7 7E15 100C CD36 69B1
#      Subkey fingerprint: F133 3857 4B66 2389 866C  7682 BFFB D25F 78C7 AE83

* remotes/bonzini-gitlab/tags/for-upstream: (38 commits)
  meson: identify more sections of meson.build
  scsi/scsi_bus: fix races in REPORT LUNS
  virtio-scsi: use scsi_device_get
  scsi/scsi_bus: Add scsi_device_get
  scsi/scsi-bus: scsi_device_find: don't return unrealized devices
  device-core: use atomic_set on .realized property
  scsi: switch to bus->check_address
  device-core: use RCU for list of children of a bus
  device_core: use drain_call_rcu in in qmp_device_add
  scsi/scsi_bus: switch search direction in scsi_device_find
  qdev: add "check if address free" callback for buses
  qemu-iotests, qtest: rewrite test 067 as a qtest
  qtest: check that drives are really appearing and disappearing
  qtest: switch users back to qtest_qmp_receive
  device-plug-test: use qtest_qmp to send the device_del command
  qtest: remove qtest_qmp_receive_success
  qtest: Reintroduce qtest_qmp_receive with QMP event buffering
  qtest: rename qtest_qmp_receive to qtest_qmp_receive_dict
  meson.build: Re-enable KVM support for MIPS
  build-sys: fix git version from -version
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 84 insertions, 0 deletions

diff --git a/docs/devel/qtest.rst b/docs/devel/qtest.rst
new file mode 100644
index 0000000000..97c5a75626
--- /dev/null
+++ b/docs/devel/qtest.rst
@@ -0,0 +1,84 @@
+========================================
+QTest Device Emulation Testing Framework
+========================================
+
+QTest is a device emulation testing framework.  It can be very useful to test
+device models; it could also control certain aspects of QEMU (such as virtual
+clock stepping), with a special purpose "qtest" protocol.  Refer to
+:ref:`qtest-protocol` for more details of the protocol.
+
+QTest cases can be executed with
+
+.. code::
+
+   make check-qtest
+
+The QTest library is implemented by ``tests/qtest/libqtest.c`` and the API is
+defined in ``tests/qtest/libqtest.h``.
+
+Consider adding a new QTest case when you are introducing a new virtual
+hardware, or extending one if you are adding functionalities to an existing
+virtual device.
+
+On top of libqtest, a higher level library, ``libqos``, was created to
+encapsulate common tasks of device drivers, such as memory management and
+communicating with system buses or devices. Many virtual device tests use
+libqos instead of directly calling into libqtest.
+
+Steps to add a new QTest case are:
+
+1. Create a new source file for the test. (More than one file can be added as
+   necessary.) For example, ``tests/qtest/foo-test.c``.
+
+2. Write the test code with the glib and libqtest/libqos API. See also existing
+   tests and the library headers for reference.
+
+3. Register the new test in ``tests/qtest/meson.build``. Add the test
+   executable name to an appropriate ``qtests_*`` variable. There is
+   one variable per architecture, plus ``qtests_generic`` for tests
+   that can be run for all architectures.  For example::
+
+     qtests_generic = [
+       ...
+       'foo-test',
+       ...
+     ]
+
+4. If the test has more than one source file or needs to be linked with any
+   dependency other than ``qemuutil`` and ``qos``, list them in the ``qtests``
+   dictionary.  For example a test that needs to use the ``QIO`` library
+   will have an entry like::
+
+     {
+       ...
+       'foo-test': [io],
+       ...
+     }
+
+Debugging a QTest failure is slightly harder than the unit test because the
+tests look up QEMU program names in the environment variables, such as
+``QTEST_QEMU_BINARY`` and ``QTEST_QEMU_IMG``, and also because it is not easy
+to attach gdb to the QEMU process spawned from the test. But manual invoking
+and using gdb on the test is still simple to do: find out the actual command
+from the output of
+
+.. code::
+
+  make check-qtest V=1
+
+which you can run manually.
+
+
+.. _qtest-protocol:
+
+QTest Protocol
+--------------
+
+.. kernel-doc:: softmmu/qtest.c
+   :doc: QTest Protocol
+
+
+libqtest API reference
+----------------------
+
+.. kernel-doc:: tests/qtest/libqos/libqtest.h