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authorRichard Henderson <richard.henderson@linaro.org>2023-07-04 08:36:44 +0200
committerRichard Henderson <richard.henderson@linaro.org>2023-07-04 08:36:44 +0200
commit2a6ae69154542caa91dd17c40fd3f5ffbec300de (patch)
tree137f02613260faea2e771cb0df1d9e896f571a1b /docs/devel
parentd145c0da22cde391d8c6672d33146ce306e8bf75 (diff)
parenta6341482695e1d15f11915f12dba98724efb0697 (diff)
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Merge tag 'pull-maintainer-ominbus-030723-1' of https://gitlab.com/stsquad/qemu into staging
maintainer updates: testing, fuzz, plugins, docs, gdbstub - clean up gitlab artefact handling - ensure gitlab publishes artefacts with coverage data - reduce testing scope for coverage job - mention CI pipeline in developer docs - add ability to add plugin args to check-tcg - fix some memory leaks and UB in tests - suppress xcb leaks from fuzzing output - add a test-fuzz to mirror the CI run - allow lci-refresh to be run in $SRC - update lcitool to latest version - add qemu-minimal package set with gcc-native - convert riscv64-cross to lcitool - update sbsa-ref tests - don't include arm_casq_ptw emulation unless TCG - convert plugins to use g_memdup2 - ensure plugins instrument SVE helper mem access - improve documentation of QOM/QDEV - make gdbstub send stop responses when it should - report user-mode pid in gdbstub - add support for info proc mappings in gdbstub # -----BEGIN PGP SIGNATURE----- # # iQEzBAABCgAdFiEEZoWumedRZ7yvyN81+9DbCVqeKkQFAmSiuH4ACgkQ+9DbCVqe # KkRt0Qf+N0oD/VuEcRSxK1bWlLtf5nxQpPKKzkRItPc5jqJnLWa/gh21sfQgs5Uq # BczAT+JfgTnMozbq0mjvQ+uAGI4MHzBs+UAn60+ZcXfk2inyk77XKBEoHOFuK1ry # rgQ4+p21/hcZedDiDLnLSfbGfUU0KkM/pbAegOz7HO0EQDV0CSXqeAW3WAuM1lne # +YmXkKwoFI1V8HvslzCT12GFiaUfmSSBtASqWcf67Ief97K24+rpkAVM7JChLm5X # fC1MOFNuNYV+jO+9U3KIs15P1WH12oMcpNUY+KqQ5ZWovBg83yOLtKY1o3f6Z2Y+ # iQgFJr6F8ZVBdKNJtqVi8DkbiFfbsA== # =Ho/h # -----END PGP SIGNATURE----- # gpg: Signature made Mon 03 Jul 2023 02:01:02 PM CEST # gpg: using RSA key 6685AE99E75167BCAFC8DF35FBD0DB095A9E2A44 # gpg: Good signature from "Alex Bennée (Master Work Key) <alex.bennee@linaro.org>" [undefined] # gpg: WARNING: This key is not certified with a trusted signature! # gpg: There is no indication that the signature belongs to the owner. # Primary key fingerprint: 6685 AE99 E751 67BC AFC8 DF35 FBD0 DB09 5A9E 2A44 * tag 'pull-maintainer-ominbus-030723-1' of https://gitlab.com/stsquad/qemu: (38 commits) tests/tcg: Add a test for info proc mappings docs: Document security implications of debugging gdbstub: Add support for info proc mappings gdbstub: Report the actual qemu-user pid gdbstub: Expose gdb_get_process() and gdb_get_first_cpu_in_process() linux-user: Emulate /proc/self/smaps linux-user: Add "safe" parameter to do_guest_openat() linux-user: Expose do_guest_openat() and do_guest_readlink() gdbstub: clean-up vcont handling to avoid goto gdbstub: Permit reverse step/break to provide stop response gdbstub: lightly refactor connection to avoid snprintf docs/devel: introduce some key concepts for QOM development docs/devel: split qom-api reference into new file docs/devel/qom.rst: Correct code style include/hw/qdev-core: fixup kerneldoc annotations include/migration: mark vmstate_register() as a legacy function docs/devel: add some front matter to the devel index plugins: update lockstep to use g_memdup2 plugins: fix memory leak while parsing options plugins: force slow path when plugins instrument memory ops ... Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Diffstat (limited to 'docs/devel')
-rw-r--r--docs/devel/index-api.rst2
-rw-r--r--docs/devel/index-process.rst2
-rw-r--r--docs/devel/index-tcg.rst2
-rw-r--r--docs/devel/index.rst24
-rw-r--r--docs/devel/qdev-api.rst7
-rw-r--r--docs/devel/qom-api.rst9
-rw-r--r--docs/devel/qom.rst65
-rw-r--r--docs/devel/tcg.rst2
-rw-r--r--docs/devel/testing.rst6
9 files changed, 108 insertions, 11 deletions
diff --git a/docs/devel/index-api.rst b/docs/devel/index-api.rst
index 7108821..539ad29 100644
--- a/docs/devel/index-api.rst
+++ b/docs/devel/index-api.rst
@@ -11,5 +11,7 @@ generated from in-code annotations to function prototypes.
loads-stores
memory
modules
+ qom-api
+ qdev-api
ui
zoned-storage
diff --git a/docs/devel/index-process.rst b/docs/devel/index-process.rst
index d50dd74..362f97e 100644
--- a/docs/devel/index-process.rst
+++ b/docs/devel/index-process.rst
@@ -1,3 +1,5 @@
+.. _development_process:
+
QEMU Community Processes
------------------------
diff --git a/docs/devel/index-tcg.rst b/docs/devel/index-tcg.rst
index b44ff8b..a992844 100644
--- a/docs/devel/index-tcg.rst
+++ b/docs/devel/index-tcg.rst
@@ -1,3 +1,5 @@
+.. _tcg:
+
TCG Emulation
-------------
diff --git a/docs/devel/index.rst b/docs/devel/index.rst
index 09cfb32..abf6045 100644
--- a/docs/devel/index.rst
+++ b/docs/devel/index.rst
@@ -2,10 +2,30 @@
Developer Information
---------------------
-This section of the manual documents various parts of the internals of QEMU.
-You only need to read it if you are interested in reading or
+This section of the manual documents various parts of the internals of
+QEMU. You only need to read it if you are interested in reading or
modifying QEMU's source code.
+QEMU is a large and mature project with a number of complex subsystems
+that can be overwhelming to understand. The development documentation
+is not comprehensive but hopefully presents enough to get you started.
+If there are areas that are unclear please reach out either via the
+IRC channel or mailing list and hopefully we can improve the
+documentation for future developers.
+
+All developers will want to familiarise themselves with
+:ref:`development_process` and how the community interacts. Please pay
+particular attention to the :ref:`coding-style` and
+:ref:`submitting-a-patch` sections to avoid common pitfalls.
+
+If you wish to implement a new hardware model you will want to read
+through the :ref:`qom` documentation to understand how QEMU's object
+model works.
+
+Those wishing to enhance or add new CPU emulation capabilities will
+want to read our :ref:`tcg` documentation, especially the overview of
+the :ref:`tcg_internals`.
+
.. toctree::
:maxdepth: 1
diff --git a/docs/devel/qdev-api.rst b/docs/devel/qdev-api.rst
new file mode 100644
index 0000000..3f35eea
--- /dev/null
+++ b/docs/devel/qdev-api.rst
@@ -0,0 +1,7 @@
+.. _qdev-api:
+
+================================
+QEMU Device (qdev) API Reference
+================================
+
+.. kernel-doc:: include/hw/qdev-core.h
diff --git a/docs/devel/qom-api.rst b/docs/devel/qom-api.rst
new file mode 100644
index 0000000..ed1f17e
--- /dev/null
+++ b/docs/devel/qom-api.rst
@@ -0,0 +1,9 @@
+.. _qom-api:
+
+=====================================
+QEMU Object Model (QOM) API Reference
+=====================================
+
+This is the complete API documentation for :ref:`qom`.
+
+.. kernel-doc:: include/qom/object.h
diff --git a/docs/devel/qom.rst b/docs/devel/qom.rst
index c923795..0b50642 100644
--- a/docs/devel/qom.rst
+++ b/docs/devel/qom.rst
@@ -13,6 +13,24 @@ features:
- System for dynamically registering types
- Support for single-inheritance of types
- Multiple inheritance of stateless interfaces
+- Mapping internal members to publicly exposed properties
+
+The root object class is TYPE_OBJECT which provides for the basic
+object methods.
+
+The QOM tree
+============
+
+The QOM tree is a composition tree which represents all of the objects
+that make up a QEMU "machine". You can view this tree by running
+``info qom-tree`` in the :ref:`QEMU monitor`. It will contain both
+objects created by the machine itself as well those created due to
+user configuration.
+
+Creating a QOM class
+====================
+
+A simple minimal device implementation may look something like bellow:
.. code-block:: c
:caption: Creating a minimal type
@@ -26,7 +44,7 @@ features:
typedef DeviceClass MyDeviceClass;
typedef struct MyDevice
{
- DeviceState parent;
+ DeviceState parent_obj;
int reg0, reg1, reg2;
} MyDevice;
@@ -48,6 +66,12 @@ In the above example, we create a simple type that is described by #TypeInfo.
#TypeInfo describes information about the type including what it inherits
from, the instance and class size, and constructor/destructor hooks.
+The TYPE_DEVICE class is the parent class for all modern devices
+implemented in QEMU and adds some specific methods to handle QEMU
+device model. This includes managing the lifetime of devices from
+creation through to when they become visible to the guest and
+eventually unrealized.
+
Alternatively several static types could be registered using helper macro
DEFINE_TYPES()
@@ -98,7 +122,7 @@ when the object is needed.
module_obj(TYPE_MY_DEVICE);
Class Initialization
-====================
+--------------------
Before an object is initialized, the class for the object must be
initialized. There is only one class object for all instance objects
@@ -147,7 +171,7 @@ will also have a wrapper function to call it easily:
typedef struct MyDeviceClass
{
- DeviceClass parent;
+ DeviceClass parent_class;
void (*frobnicate) (MyDevice *obj);
} MyDeviceClass;
@@ -168,7 +192,7 @@ will also have a wrapper function to call it easily:
}
Interfaces
-==========
+----------
Interfaces allow a limited form of multiple inheritance. Instances are
similar to normal types except for the fact that are only defined by
@@ -182,7 +206,7 @@ an argument to a method on its corresponding SomethingIfClass, or to
dynamically cast it to an object that implements the interface.
Methods
-=======
+-------
A *method* is a function within the namespace scope of
a class. It usually operates on the object instance by passing it as a
@@ -275,8 +299,8 @@ Alternatively, object_class_by_name() can be used to obtain the class and
its non-overridden methods for a specific type. This would correspond to
``MyClass::method(...)`` in C++.
-The first example of such a QOM method was #CPUClass.reset,
-another example is #DeviceClass.realize.
+One example of such methods is ``DeviceClass.reset``. More examples
+can be found at :ref:`device-life-cycle`.
Standard type declaration and definition macros
===============================================
@@ -382,9 +406,32 @@ OBJECT_DEFINE_ABSTRACT_TYPE() macro can be used instead:
OBJECT_DEFINE_ABSTRACT_TYPE(MyDevice, my_device,
MY_DEVICE, DEVICE)
+.. _device-life-cycle:
+
+Device Life-cycle
+=================
+
+As class initialisation cannot fail devices have an two additional
+methods to handle the creation of dynamic devices. The ``realize``
+function is called with ``Error **`` pointer which should be set if
+the device cannot complete its setup. Otherwise on successful
+completion of the ``realize`` method the device object is added to the
+QOM tree and made visible to the guest.
+
+The reverse function is ``unrealize`` and should be were clean-up
+code lives to tidy up after the system is done with the device.
+
+All devices can be instantiated by C code, however only some can
+created dynamically via the command line or monitor.
+Likewise only some can be unplugged after creation and need an
+explicit ``unrealize`` implementation. This is determined by the
+``user_creatable`` variable in the root ``DeviceClass`` structure.
+Devices can only be unplugged if their ``parent_bus`` has a registered
+``HotplugHandler``.
API Reference
--------------
+=============
-.. kernel-doc:: include/qom/object.h
+See the :ref:`QOM API<qom-api>` and :ref:`QDEV API<qdev-api>`
+documents for the complete API description.
diff --git a/docs/devel/tcg.rst b/docs/devel/tcg.rst
index b4096a1..2786f2f 100644
--- a/docs/devel/tcg.rst
+++ b/docs/devel/tcg.rst
@@ -1,3 +1,5 @@
+.. _tcg_internals:
+
====================
Translator Internals
====================
diff --git a/docs/devel/testing.rst b/docs/devel/testing.rst
index e85e26c..fb651ea 100644
--- a/docs/devel/testing.rst
+++ b/docs/devel/testing.rst
@@ -485,6 +485,12 @@ first to contribute the mapping to the ``libvirt-ci`` project:
`CI <https://www.qemu.org/docs/master/devel/ci.html>`__ documentation
page on how to trigger gitlab CI pipelines on your change.
+ * Please also trigger gitlab container generation pipelines on your change
+ for as many OS distros as practical to make sure that there are no
+ obvious breakages when adding the new pre-requisite. Please see
+ `CI <https://www.qemu.org/docs/master/devel/ci.html>`__ documentation
+ page on how to trigger gitlab CI pipelines on your change.
+
For enterprise distros that default to old, end-of-life versions of the
Python runtime, QEMU uses a separate set of mappings that work with more
recent versions. These can be found in ``tests/lcitool/mappings.yml``.