qdev: Replace cannot_instantiate_with_device_add_yet with !user_creatable

cannot_instantiate_with_device_add_yet was introduced by commit
efec3dd631d94160288392721a5f9c39e50fb2bc to replace no_user. It was
supposed to be a temporary measure.

When it was introduced, we had 54
cannot_instantiate_with_device_add_yet=true lines in the code.
Today (3 years later) this number has not shrunk: we now have
57 cannot_instantiate_with_device_add_yet=true lines. I think it
is safe to say it is not a temporary measure, and we won't see
the flag go away soon.

Instead of a long field name that misleads people to believe it
is temporary, replace it a shorter and less misleading field:
user_creatable.

Except for code comments, changes were generated using the
following Coccinelle patch:

  @@
  expression DC;
  @@
  (
  -DC->cannot_instantiate_with_device_add_yet = false;
  +DC->user_creatable = true;
  |
  -DC->cannot_instantiate_with_device_add_yet = true;
  +DC->user_creatable = false;
  )

  @@
  typedef ObjectClass;
  expression dc;
  identifier class, data;
  @@
   static void device_class_init(ObjectClass *class, void *data)
   {
   ...
   dc->hotpluggable = true;
  +dc->user_creatable = true;
   ...
   }

  @@
  @@
   struct DeviceClass {
   ...
  -bool cannot_instantiate_with_device_add_yet;
  +bool user_creatable;
   ...
  }

  @@
  expression DC;
  @@
  (
  -!DC->cannot_instantiate_with_device_add_yet
  +DC->user_creatable
  |
  -DC->cannot_instantiate_with_device_add_yet
  +!DC->user_creatable
  )

Cc: Alistair Francis <alistair.francis@xilinx.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Marcel Apfelbaum <marcel@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Thomas Huth <thuth@redhat.com>
Acked-by: Alistair Francis <alistair.francis@xilinx.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>
Acked-by: Marcel Apfelbaum <marcel@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20170503203604.31462-2-ehabkost@redhat.com>
[ehabkost: kept "TODO remove once we're there" comment]
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>

2 files changed, 7 insertions, 6 deletions

diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h
index 4bf86b0..e69489e 100644
--- a/include/hw/qdev-core.h
+++ b/include/hw/qdev-core.h
@@ -103,16 +103,17 @@ typedef struct DeviceClass {
     Property *props;
 
     /*
-     * Shall we hide this device model from -device / device_add?
+     * Can this device be instantiated with -device / device_add?
      * All devices should support instantiation with device_add, and
      * this flag should not exist.  But we're not there, yet.  Some
      * devices fail to instantiate with cryptic error messages.
      * Others instantiate, but don't work.  Exposing users to such
-     * behavior would be cruel; this flag serves to protect them.  It
-     * should never be set without a comment explaining why it is set.
+     * behavior would be cruel; clearing this flag will protect them.
+     * It should never be cleared without a comment explaining why it
+     * is cleared.
      * TODO remove once we're there
      */
-    bool cannot_instantiate_with_device_add_yet;
+    bool user_creatable;
     bool hotpluggable;
 
     /* callbacks */
diff --git a/include/hw/qdev-properties.h b/include/hw/qdev-properties.h
index 1d69fa7..d206fc9 100644
--- a/include/hw/qdev-properties.h
+++ b/include/hw/qdev-properties.h
@@ -134,12 +134,12 @@ extern PropertyInfo qdev_prop_arraylen;
  *   device_add, so add code like this:
  *   |* Reason: pointer property "NAME-OF-YOUR-PROP" *|
  *   DeviceClass *dc = DEVICE_CLASS(class);
- *   dc->cannot_instantiate_with_device_add_yet = true;
+ *   dc->user_creatable = false;
  *
  * - If the property may safely remain null, document it like this:
  *   |*
  *    * Note: pointer property "interrupt_vector" may remain null, thus
- *    * no need for dc->cannot_instantiate_with_device_add_yet = true;
+ *    * no need for dc->user_creatable = false;
  *    *|
  */
 #define DEFINE_PROP_PTR(_n, _s, _f)             \