[RFC 01/10] virtio: get class_id and pci device id by the virtio id

[Longpeng(Mike)]

From: Longpeng <longpeng2@huawei.com>

Add helpers to get the "Transitional PCI Device ID" and "class_id" of the
deivce which is specificed by the "Virtio Device ID".

These helpers will be used to build the generic vDPA device later.

Signed-off-by: Longpeng <longpeng2@huawei.com>
---
 hw/virtio/virtio-pci.c | 93 ++++++++++++++++++++++++++++++++++++++++++
 hw/virtio/virtio-pci.h |  4 ++
 2 files changed, 97 insertions(+)

diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
index 750aa47ec1..843085c4ea 100644
--- a/hw/virtio/virtio-pci.c
+++ b/hw/virtio/virtio-pci.c
@@ -19,6 +19,7 @@
 
 #include "exec/memop.h"
 #include "standard-headers/linux/virtio_pci.h"
+#include "standard-headers/linux/virtio_ids.h"
 #include "hw/boards.h"
 #include "hw/virtio/virtio.h"
 #include "migration/qemu-file-types.h"
@@ -213,6 +214,95 @@ static int virtio_pci_load_queue(DeviceState *d, int n, 
QEMUFile *f)
     return 0;
 }
 
+typedef struct VirtIOPCIIDInfo {
+    uint16_t vdev_id; /* virtio id */
+    uint16_t pdev_id; /* pci device id */
+    uint16_t class_id;
+} VirtIOPCIIDInfo;
+
+static const VirtIOPCIIDInfo virtio_pci_id_info[] = {
+    {
+        .vdev_id = VIRTIO_ID_NET,
+        .pdev_id = PCI_DEVICE_ID_VIRTIO_NET,
+        .class_id = PCI_CLASS_NETWORK_ETHERNET,
+    },
+    {
+        .vdev_id = VIRTIO_ID_BLOCK,
+        .pdev_id = PCI_DEVICE_ID_VIRTIO_BLOCK,
+        .class_id = PCI_CLASS_STORAGE_SCSI,
+    },
+    {
+        .vdev_id = VIRTIO_ID_CONSOLE,
+        .pdev_id = PCI_DEVICE_ID_VIRTIO_CONSOLE,
+        .class_id = PCI_CLASS_COMMUNICATION_OTHER,
+    },
+    {
+        .vdev_id = VIRTIO_ID_SCSI,
+        .pdev_id = PCI_DEVICE_ID_VIRTIO_SCSI,
+        .class_id = PCI_CLASS_STORAGE_SCSI,
+    },
+    {
+        .vdev_id = VIRTIO_ID_9P,
+        .pdev_id = PCI_DEVICE_ID_VIRTIO_9P,
+        .class_id = PCI_BASE_CLASS_NETWORK,
+    },
+    {
+        .vdev_id = VIRTIO_ID_VSOCK,
+        .pdev_id = PCI_DEVICE_ID_VIRTIO_VSOCK,
+        .class_id = PCI_CLASS_COMMUNICATION_OTHER,
+    },
+    {
+        .vdev_id = VIRTIO_ID_IOMMU,
+        .pdev_id = PCI_DEVICE_ID_VIRTIO_IOMMU,
+        .class_id = PCI_CLASS_OTHERS,
+    },
+    {
+        .vdev_id = VIRTIO_ID_MEM,
+        .pdev_id = PCI_DEVICE_ID_VIRTIO_MEM,
+        .class_id = PCI_CLASS_OTHERS,
+    },
+    {
+        .vdev_id = VIRTIO_ID_PMEM,
+        .pdev_id = PCI_DEVICE_ID_VIRTIO_PMEM,
+        .class_id = PCI_CLASS_OTHERS,
+    },
+    {
+        .vdev_id = VIRTIO_ID_RNG,
+        .pdev_id = PCI_DEVICE_ID_VIRTIO_RNG,
+        .class_id = PCI_CLASS_OTHERS,
+    },
+    {
+        .vdev_id = VIRTIO_ID_BALLOON,
+        .pdev_id = PCI_DEVICE_ID_VIRTIO_BALLOON,
+        .class_id = PCI_CLASS_OTHERS,
+    },
+};
+
+static VirtIOPCIIDInfo virtio_pci_get_id_info(uint16_t vdev_id)
+{
+    VirtIOPCIIDInfo info = {};
+    int i;
+
+    for (i = 0; i < ARRAY_SIZE(virtio_pci_id_info); i++) {
+        if (virtio_pci_id_info[i].vdev_id == vdev_id) {
+            info = virtio_pci_id_info[i];
+            break;
+        }
+    }
+
+    return info;
+}
+
+uint16_t virtio_pci_get_pci_devid(uint16_t device_id)
+{
+    return virtio_pci_get_id_info(device_id).pdev_id;
+}
+
+uint16_t virtio_pci_get_class_id(uint16_t device_id)
+{
+    return virtio_pci_get_id_info(device_id).class_id;
+}
+
 static bool virtio_pci_ioeventfd_enabled(DeviceState *d)
 {
     VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);
@@ -1674,6 +1764,9 @@ static void virtio_pci_device_plugged(DeviceState *d, 
Error **errp)
          * is set to PCI_SUBVENDOR_ID_REDHAT_QUMRANET by default.
          */
         pci_set_word(config + PCI_SUBSYSTEM_ID, virtio_bus_get_vdev_id(bus));
+        if (proxy->pdev_id) {
+            pci_config_set_device_id(config, proxy->pdev_id);
+        }
     } else {
         /* pure virtio-1.0 */
         pci_set_word(config + PCI_VENDOR_ID,
diff --git a/hw/virtio/virtio-pci.h b/hw/virtio/virtio-pci.h
index 2446dcd9ae..06aa59436e 100644
--- a/hw/virtio/virtio-pci.h
+++ b/hw/virtio/virtio-pci.h
@@ -146,6 +146,7 @@ struct VirtIOPCIProxy {
     bool disable_modern;
     bool ignore_backend_features;
     OnOffAuto disable_legacy;
+    uint16_t pdev_id;
     uint32_t class_code;
     uint32_t nvectors;
     uint32_t dfselect;
@@ -158,6 +159,9 @@ struct VirtIOPCIProxy {
     VirtioBusState bus;
 };
 
+uint16_t virtio_pci_get_pci_devid(uint16_t device_id);
+uint16_t virtio_pci_get_class_id(uint16_t device_id);
+
 static inline bool virtio_pci_modern(VirtIOPCIProxy *proxy)
 {
     return !proxy->disable_modern;
-- 
2.23.0