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, 23 insertions, 1 deletions

diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h
index 72064f4dd4..868973319e 100644
--- a/include/hw/qdev-core.h
+++ b/include/hw/qdev-core.h
@@ -3,6 +3,8 @@
 
 #include "qemu/queue.h"
 #include "qemu/bitmap.h"
+#include "qemu/rcu.h"
+#include "qemu/rcu_queue.h"
 #include "qom/object.h"
 #include "hw/hotplug.h"
 #include "hw/resettable.h"
@@ -161,6 +163,8 @@ struct NamedClockList {
 /**
  * DeviceState:
  * @realized: Indicates whether the device has been fully constructed.
+ *            When accessed outsize big qemu lock, must be accessed with
+ *            atomic_load_acquire()
  * @reset: ResettableState for the device; handled by Resettable interface.
  *
  * This structure should not be accessed directly.  We declare it here
@@ -210,13 +214,24 @@ struct BusClass {
     /* FIXME first arg should be BusState */
     void (*print_dev)(Monitor *mon, DeviceState *dev, int indent);
     char *(*get_dev_path)(DeviceState *dev);
+
     /*
      * This callback is used to create Open Firmware device path in accordance
      * with OF spec http://forthworks.com/standards/of1275.pdf. Individual bus
      * bindings can be found at http://playground.sun.com/1275/bindings/.
      */
     char *(*get_fw_dev_path)(DeviceState *dev);
+
     void (*reset)(BusState *bus);
+
+    /*
+     * Return whether the device can be added to @bus,
+     * based on the address that was set (via device properties)
+     * before realize.  If not, on return @errp contains the
+     * human-readable error message.
+     */
+    bool (*check_address)(BusState *bus, DeviceState *dev, Error **errp);
+
     BusRealize realize;
     BusUnrealize unrealize;
 
@@ -227,6 +242,7 @@ struct BusClass {
 };
 
 typedef struct BusChild {
+    struct rcu_head rcu;
     DeviceState *child;
     int index;
     QTAILQ_ENTRY(BusChild) sibling;
@@ -247,6 +263,12 @@ struct BusState {
     int max_index;
     bool realized;
     int num_children;
+
+    /*
+     * children is a RCU QTAILQ, thus readers must use RCU to access it,
+     * and writers must hold the big qemu lock
+     */
+
     QTAILQ_HEAD(, BusChild) children;
     QLIST_ENTRY(BusState) sibling;
     ResettableState reset;
@@ -788,7 +810,7 @@ const char *qdev_fw_name(DeviceState *dev);
 Object *qdev_get_machine(void);
 
 /* FIXME: make this a link<> */
-void qdev_set_parent_bus(DeviceState *dev, BusState *bus);
+bool qdev_set_parent_bus(DeviceState *dev, BusState *bus, Error **errp);
 
 extern bool qdev_hotplug;
 extern bool qdev_hot_removed;