[PATCH v4 1/2] qdev-properties: Add a new macro with bitmask check for uint64_t property

[Yang Weijiang <weijiang.yang@intel.com>]

The DEFINE_PROP_UINT64_CHECKMASK maro applies certain mask check agaist
user-supplied property value, reject the value if it violates the bitmask.

Co-developed-by: Like Xu <like.xu@linux.intel.com>
Signed-off-by: Like Xu <like.xu@linux.intel.com>
Signed-off-by: Yang Weijiang <weijiang.yang@intel.com>
---
 hw/core/qdev-properties.c    | 19 +++++++++++++++++++
 include/hw/qdev-properties.h | 12 ++++++++++++
 2 files changed, 31 insertions(+)

diff --git a/hw/core/qdev-properties.c b/hw/core/qdev-properties.c
index 50f40949f5..343a200784 100644
--- a/hw/core/qdev-properties.c
+++ b/hw/core/qdev-properties.c
@@ -428,6 +428,25 @@ const PropertyInfo qdev_prop_int64 = {
     .set_default_value = qdev_propinfo_set_default_value_int,
 };
 
+static void set_uint64_checkmask(Object *obj, Visitor *v, const char *name,
+                      void *opaque, Error **errp)
+{
+    Property *prop = opaque;
+    uint64_t *ptr = object_field_prop_ptr(obj, prop);
+
+    visit_type_uint64(v, name, ptr, errp);
+    if (*ptr & ~prop->bitmask) {
+        error_setg(errp, "Property value for '%s' violates bitmask '0x%lx'",
+                   name, prop->bitmask);
+    }
+}
+
+const PropertyInfo qdev_prop_uint64_checkmask = {
+    .name  = "uint64",
+    .get   = get_uint64,
+    .set   = set_uint64_checkmask,
+};
+
 /* --- string --- */
 
 static void release_string(Object *obj, const char *name, void *opaque)
diff --git a/include/hw/qdev-properties.h b/include/hw/qdev-properties.h
index 0ef97d60ce..075882e8c1 100644
--- a/include/hw/qdev-properties.h
+++ b/include/hw/qdev-properties.h
@@ -17,6 +17,7 @@ struct Property {
     const PropertyInfo *info;
     ptrdiff_t    offset;
     uint8_t      bitnr;
+    uint64_t     bitmask;
     bool         set_default;
     union {
         int64_t i;
@@ -53,6 +54,7 @@ extern const PropertyInfo qdev_prop_uint16;
 extern const PropertyInfo qdev_prop_uint32;
 extern const PropertyInfo qdev_prop_int32;
 extern const PropertyInfo qdev_prop_uint64;
+extern const PropertyInfo qdev_prop_uint64_checkmask;
 extern const PropertyInfo qdev_prop_int64;
 extern const PropertyInfo qdev_prop_size;
 extern const PropertyInfo qdev_prop_string;
@@ -102,6 +104,16 @@ extern const PropertyInfo qdev_prop_link;
                 .set_default = true,                         \
                 .defval.u    = (bool)_defval)
 
+/**
+ * The DEFINE_PROP_UINT64_CHECKMASK macro checks a user-supplied value
+ * against corresponding bitmask, rejects the value if it violates.
+ * The default value is set in instance_init().
+ */
+#define DEFINE_PROP_UINT64_CHECKMASK(_name, _state, _field, _bitmask)   \
+    DEFINE_PROP(_name, _state, _field, qdev_prop_uint64_checkmask, uint64_t, \
+                .bitmask    = (_bitmask),                     \
+                .set_default = false)
+
 #define PROP_ARRAY_LEN_PREFIX "len-"
 
 /**
-- 
2.21.1