vDPA/ifcvf: implement features provisioning

This commit implements features provisioning for ifcvf, that means:
1)checkk whether the provisioned features are supported by
the management device
2)vDPA device only presents selected feature bits

Examples:
a)The management device supported features:
$ vdpa mgmtdev show pci/0000:01:00.5
pci/0000:01:00.5:
  supported_classes net
  max_supported_vqs 9
  dev_features MTU MAC MRG_RXBUF CTRL_VQ MQ ANY_LAYOUT VERSION_1 ACCESS_PLATFORM

b)Provision a vDPA device with all supported features:
$ vdpa dev add name vdpa0 mgmtdev pci/0000:01:00.5
$ vdpa/vdpa dev config show vdpa0
vdpa0: mac 00:e8:ca:11:be:05 link up link_announce false max_vq_pairs 4 mtu 1500
  negotiated_features MRG_RXBUF CTRL_VQ MQ VERSION_1 ACCESS_PLATFORM

c)Provision a vDPA device with a subset of the supported features:
$ vdpa dev add name vdpa0 mgmtdev pci/0000:01:00.5 device_features 0x300020020
$ vdpa dev config show vdpa0
mac 00:e8:ca:11:be:05 link up link_announce false
  negotiated_features CTRL_VQ VERSION_1 ACCESS_PLATFORM
Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Message-Id: <20221125145724.1129962-13-lingshan.zhu@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

drivers/vdpa/ifcvf/ifcvf_base.c

@@ -206,7 +206,7 @@ u64 ifcvf_get_hw_features(struct ifcvf_hw *hw)
 
 u64 ifcvf_get_features(struct ifcvf_hw *hw)
 {
-	return hw->hw_features;
+	return hw->dev_features;
 }
 
 int ifcvf_verify_min_features(struct ifcvf_hw *hw, u64 features)

drivers/vdpa/ifcvf/ifcvf_base.h

@@ -19,6 +19,7 @@
 #include <uapi/linux/virtio_blk.h>
 #include <uapi/linux/virtio_config.h>
 #include <uapi/linux/virtio_pci.h>
+#include <uapi/linux/vdpa.h>
 
 #define N3000_DEVICE_ID		0x1041
 #define N3000_SUBSYS_DEVICE_ID	0x001A
@@ -75,6 +76,8 @@ struct ifcvf_hw {
 	u32 dev_type;
 	u64 req_features;
 	u64 hw_features;
+	/* provisioned device features */
+	u64 dev_features;
 	struct virtio_pci_common_cfg __iomem *common_cfg;
 	void __iomem *dev_cfg;
 	struct vring_info vring[IFCVF_MAX_QUEUES];

drivers/vdpa/ifcvf/ifcvf_main.c

@@ -743,6 +743,7 @@ static int ifcvf_vdpa_dev_add(struct vdpa_mgmt_dev *mdev, const char *name,
 	struct vdpa_device *vdpa_dev;
 	struct pci_dev *pdev;
 	struct ifcvf_hw *vf;
+	u64 device_features;
 	int ret;
 
 	ifcvf_mgmt_dev = container_of(mdev, struct ifcvf_vdpa_mgmt_dev, mdev);
@@ -762,6 +763,17 @@ static int ifcvf_vdpa_dev_add(struct vdpa_mgmt_dev *mdev, const char *name,
 	adapter->vf = vf;
 	vdpa_dev = &adapter->vdpa;
 
+	device_features = vf->hw_features;
+	if (config->mask & BIT_ULL(VDPA_ATTR_DEV_FEATURES)) {
+		if (config->device_features & ~device_features) {
+			IFCVF_ERR(pdev, "The provisioned features 0x%llx are not supported by this device with features 0x%llx\n",
+				  config->device_features, device_features);
+			return -EINVAL;
+		}
+		device_features &= config->device_features;
+	}
+	vf->dev_features = device_features;
+
 	if (name)
 		ret = dev_set_name(&vdpa_dev->dev, "%s", name);
 	else
@@ -866,6 +878,7 @@ static int ifcvf_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	ifcvf_mgmt_dev->mdev.device = dev;
 	ifcvf_mgmt_dev->mdev.max_supported_vqs = vf->nr_vring;
 	ifcvf_mgmt_dev->mdev.supported_features = vf->hw_features;
+	ifcvf_mgmt_dev->mdev.config_attr_mask = (1 << VDPA_ATTR_DEV_FEATURES);
 
 	ret = vdpa_mgmtdev_register(&ifcvf_mgmt_dev->mdev);
 	if (ret) {