From 5cc56cc6872122af318f07088b7d599c3781719f Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Mon, 17 Jul 2017 13:36:06 +0100 Subject: qdev: support properties which don't set a default value MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In some situations it's useful to have a qdev property which doesn't automatically set its default value when qdev_property_add_static is called (for instance when the default value is not constant). Support this by adding a flag to the Property struct indicating whether to set the default value. This replaces the existing test for whether the PropertyInfo set_default_value function pointer is NULL, and we set the .set_default field to true for all those cases of struct Property which use a PropertyInfo with a non-NULL set_default_value, so behaviour remains the same as before. This gives us the semantics of: * if .set_default is true, then .info->set_default_value must be not NULL, and .defval is used as the the default value of the property * otherwise, the property system does not set any default, and the field will retain whatever initial value it was given by the device's .instance_init method We define two new macros DEFINE_PROP_SIGNED_NODEFAULT and DEFINE_PROP_UNSIGNED_NODEFAULT, to cover the most plausible use cases of wanting to set an integer property with no default value. Suggested-by: Markus Armbruster Signed-off-by: Peter Maydell Reviewed-by: Marc-André Lureau Reviewed-by: Markus Armbruster Message-id: 1499788408-10096-3-git-send-email-peter.maydell@linaro.org --- hw/core/qdev.c | 2 +- include/hw/qdev-core.h | 10 ++++++++++ include/hw/qdev-properties.h | 20 ++++++++++++++++++++ 3 files changed, 31 insertions(+), 1 deletion(-) diff --git a/hw/core/qdev.c b/hw/core/qdev.c index ec63fe0..606ab53 100644 --- a/hw/core/qdev.c +++ b/hw/core/qdev.c @@ -800,7 +800,7 @@ void qdev_property_add_static(DeviceState *dev, Property *prop, prop->info->description, &error_abort); - if (prop->info->set_default_value) { + if (prop->set_default) { prop->info->set_default_value(obj, prop); } } diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h index 5348815..ae31728 100644 --- a/include/hw/qdev-core.h +++ b/include/hw/qdev-core.h @@ -221,11 +221,21 @@ struct BusState { QLIST_ENTRY(BusState) sibling; }; +/** + * Property: + * @set_default: true if the default value should be set from @defval, + * in which case @info->set_default_value must not be NULL + * (if false then no default value is set by the property system + * and the field retains whatever value it was given by instance_init). + * @defval: default value for the property. This is used only if @set_default + * is true. + */ struct Property { const char *name; const PropertyInfo *info; ptrdiff_t offset; uint8_t bitnr; + bool set_default; union { int64_t i; uint64_t u; diff --git a/include/hw/qdev-properties.h b/include/hw/qdev-properties.h index 12c0c7b..3929796 100644 --- a/include/hw/qdev-properties.h +++ b/include/hw/qdev-properties.h @@ -44,15 +44,24 @@ extern const PropertyInfo qdev_prop_link; .info = &(_prop), \ .offset = offsetof(_state, _field) \ + type_check(_type,typeof_field(_state, _field)), \ + .set_default = true, \ .defval.i = (_type)_defval, \ } +#define DEFINE_PROP_SIGNED_NODEFAULT(_name, _state, _field, _prop, _type) { \ + .name = (_name), \ + .info = &(_prop), \ + .offset = offsetof(_state, _field) \ + + type_check(_type, typeof_field(_state, _field)), \ + } + #define DEFINE_PROP_BIT(_name, _state, _field, _bit, _defval) { \ .name = (_name), \ .info = &(qdev_prop_bit), \ .bitnr = (_bit), \ .offset = offsetof(_state, _field) \ + type_check(uint32_t,typeof_field(_state, _field)), \ + .set_default = true, \ .defval.u = (bool)_defval, \ } @@ -61,15 +70,24 @@ extern const PropertyInfo qdev_prop_link; .info = &(_prop), \ .offset = offsetof(_state, _field) \ + type_check(_type, typeof_field(_state, _field)), \ + .set_default = true, \ .defval.u = (_type)_defval, \ } +#define DEFINE_PROP_UNSIGNED_NODEFAULT(_name, _state, _field, _prop, _type) { \ + .name = (_name), \ + .info = &(_prop), \ + .offset = offsetof(_state, _field) \ + + type_check(_type, typeof_field(_state, _field)), \ + } + #define DEFINE_PROP_BIT64(_name, _state, _field, _bit, _defval) { \ .name = (_name), \ .info = &(qdev_prop_bit64), \ .bitnr = (_bit), \ .offset = offsetof(_state, _field) \ + type_check(uint64_t, typeof_field(_state, _field)), \ + .set_default = true, \ .defval.u = (bool)_defval, \ } @@ -78,6 +96,7 @@ extern const PropertyInfo qdev_prop_link; .info = &(qdev_prop_bool), \ .offset = offsetof(_state, _field) \ + type_check(bool, typeof_field(_state, _field)), \ + .set_default = true, \ .defval.u = (bool)_defval, \ } @@ -111,6 +130,7 @@ extern const PropertyInfo qdev_prop_link; _arrayfield, _arrayprop, _arraytype) { \ .name = (PROP_ARRAY_LEN_PREFIX _name), \ .info = &(qdev_prop_arraylen), \ + .set_default = true, \ .defval.u = 0, \ .offset = offsetof(_state, _field) \ + type_check(uint32_t, typeof_field(_state, _field)), \ -- cgit v1.1