diff mbox series

[RESEND,v5,1/3] qmp: remove virtio_list, search QOM tree instead

Message ID 20230926224107.2951144-2-jonah.palmer@oracle.com (mailing list archive)
State New, archived
Headers show
Series qmp, vhost-user: Remove virtio_list & update virtio introspection | expand

Commit Message

Jonah Palmer Sept. 26, 2023, 10:41 p.m. UTC 
The virtio_list duplicates information about virtio devices that already
exist in the QOM composition tree. Instead of creating this list of
realized virtio devices, search the QOM composition tree instead.

This patch modifies the QMP command qmp_x_query_virtio to instead
recursively search the QOM composition tree for devices of type
'TYPE_VIRTIO_DEVICE'. The device is also checked to ensure it's
realized.

Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
---
 hw/virtio/virtio-qmp.c | 85 ++++++++++++++----------------------------
 hw/virtio/virtio-qmp.h |  7 ----
 hw/virtio/virtio.c     |  6 ---
 3 files changed, 29 insertions(+), 69 deletions(-)
diff mbox series

Patch

diff --git a/hw/virtio/virtio-qmp.c b/hw/virtio/virtio-qmp.c
index 7515b0947b..adebf87e9b 100644
--- a/hw/virtio/virtio-qmp.c
+++ b/hw/virtio/virtio-qmp.c
@@ -667,70 +667,43 @@  VirtioDeviceFeatures *qmp_decode_features(uint16_t device_id, uint64_t bitmap)
     return features;
 }
 
+static int query_dev_child(Object *child, void *opaque)
+{
+    VirtioInfoList **vdevs = opaque;
+    Object *dev = object_dynamic_cast(child, TYPE_VIRTIO_DEVICE);
+    if (dev != NULL && DEVICE(dev)->realized) {
+        VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+        VirtioInfo *info = g_new(VirtioInfo, 1);
+
+        /* Get canonical path & name of device */
+        info->path = object_get_canonical_path(dev);
+        info->name = g_strdup(vdev->name);
+        QAPI_LIST_PREPEND(*vdevs, info);
+    }
+    return 0;
+}
+
 VirtioInfoList *qmp_x_query_virtio(Error **errp)
 {
-    VirtioInfoList *list = NULL;
-    VirtioInfo *node;
-    VirtIODevice *vdev;
+    VirtioInfoList *vdevs = NULL;
 
-    QTAILQ_FOREACH(vdev, &virtio_list, next) {
-        DeviceState *dev = DEVICE(vdev);
-        Error *err = NULL;
-        QObject *obj = qmp_qom_get(dev->canonical_path, "realized", &err);
-
-        if (err == NULL) {
-            GString *is_realized = qobject_to_json_pretty(obj, true);
-            /* virtio device is NOT realized, remove it from list */
-            if (!strncmp(is_realized->str, "false", 4)) {
-                QTAILQ_REMOVE(&virtio_list, vdev, next);
-            } else {
-                node = g_new(VirtioInfo, 1);
-                node->path = g_strdup(dev->canonical_path);
-                node->name = g_strdup(vdev->name);
-                QAPI_LIST_PREPEND(list, node);
-            }
-           g_string_free(is_realized, true);
-        }
-        qobject_unref(obj);
+    /* Query the QOM composition tree recursively for virtio devices */
+    object_child_foreach_recursive(object_get_root(), query_dev_child, &vdevs);
+    if (vdevs == NULL) {
+        error_setg(errp, "No virtio devices found");
     }
-
-    return list;
+    return vdevs;
 }
 
 VirtIODevice *qmp_find_virtio_device(const char *path)
 {
-    VirtIODevice *vdev;
-
-    QTAILQ_FOREACH(vdev, &virtio_list, next) {
-        DeviceState *dev = DEVICE(vdev);
-
-        if (strcmp(dev->canonical_path, path) != 0) {
-            continue;
-        }
-
-        Error *err = NULL;
-        QObject *obj = qmp_qom_get(dev->canonical_path, "realized", &err);
-        if (err == NULL) {
-            GString *is_realized = qobject_to_json_pretty(obj, true);
-            /* virtio device is NOT realized, remove it from list */
-            if (!strncmp(is_realized->str, "false", 4)) {
-                g_string_free(is_realized, true);
-                qobject_unref(obj);
-                QTAILQ_REMOVE(&virtio_list, vdev, next);
-                return NULL;
-            }
-            g_string_free(is_realized, true);
-        } else {
-            /* virtio device doesn't exist in QOM tree */
-            QTAILQ_REMOVE(&virtio_list, vdev, next);
-            qobject_unref(obj);
-            return NULL;
-        }
-        /* device exists in QOM tree & is realized */
-        qobject_unref(obj);
-        return vdev;
+    /* Verify the canonical path is a realized virtio device */
+    Object *dev = object_dynamic_cast(object_resolve_path(path, NULL),
+                                      TYPE_VIRTIO_DEVICE);
+    if (!dev || !DEVICE(dev)->realized) {
+        return NULL;
     }
-    return NULL;
+    return VIRTIO_DEVICE(dev);
 }
 
 VirtioStatus *qmp_x_query_virtio_status(const char *path, Error **errp)
@@ -740,7 +713,7 @@  VirtioStatus *qmp_x_query_virtio_status(const char *path, Error **errp)
 
     vdev = qmp_find_virtio_device(path);
     if (vdev == NULL) {
-        error_setg(errp, "Path %s is not a VirtIODevice", path);
+        error_setg(errp, "Path %s is not a realized VirtIODevice", path);
         return NULL;
     }
 
diff --git a/hw/virtio/virtio-qmp.h b/hw/virtio/virtio-qmp.h
index 8af5f5e65a..245a446a56 100644
--- a/hw/virtio/virtio-qmp.h
+++ b/hw/virtio/virtio-qmp.h
@@ -15,13 +15,6 @@ 
 #include "hw/virtio/virtio.h"
 #include "hw/virtio/vhost.h"
 
-#include "qemu/queue.h"
-
-typedef QTAILQ_HEAD(QmpVirtIODeviceList, VirtIODevice) QmpVirtIODeviceList;
-
-/* QAPI list of realized VirtIODevices */
-extern QmpVirtIODeviceList virtio_list;
-
 VirtIODevice *qmp_find_virtio_device(const char *path);
 VirtioDeviceStatus *qmp_decode_status(uint8_t bitmap);
 VhostDeviceProtocols *qmp_decode_protocols(uint64_t bitmap);
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index 4577f3f5b3..6df5d9bec6 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -45,8 +45,6 @@ 
 #include "standard-headers/linux/virtio_mem.h"
 #include "standard-headers/linux/virtio_vsock.h"
 
-QmpVirtIODeviceList virtio_list;
-
 /*
  * Maximum size of virtio device config space
  */
@@ -3651,7 +3649,6 @@  static void virtio_device_realize(DeviceState *dev, Error **errp)
     vdev->listener.commit = virtio_memory_listener_commit;
     vdev->listener.name = "virtio";
     memory_listener_register(&vdev->listener, vdev->dma_as);
-    QTAILQ_INSERT_TAIL(&virtio_list, vdev, next);
 }
 
 static void virtio_device_unrealize(DeviceState *dev)
@@ -3666,7 +3663,6 @@  static void virtio_device_unrealize(DeviceState *dev)
         vdc->unrealize(dev);
     }
 
-    QTAILQ_REMOVE(&virtio_list, vdev, next);
     g_free(vdev->bus_name);
     vdev->bus_name = NULL;
 }
@@ -3840,8 +3836,6 @@  static void virtio_device_class_init(ObjectClass *klass, void *data)
     vdc->stop_ioeventfd = virtio_device_stop_ioeventfd_impl;
 
     vdc->legacy_features |= VIRTIO_LEGACY_FEATURES;
-
-    QTAILQ_INIT(&virtio_list);
 }
 
 bool virtio_device_ioeventfd_enabled(VirtIODevice *vdev)