vdpa: introduce map ops

Virtio core allows the transport to provide device or transport
specific mapping functions. This patch adds this support to vDPA. We
can simply do this by allowing the vDPA parent to register a
virtio_map_ops.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20250924070045.10361-2-jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eugenio Pérez <eperezma@redhat.com>

drivers/vdpa/alibaba/eni_vdpa.c

@@ -478,7 +478,8 @@ static int eni_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 		return ret;
 
 	eni_vdpa = vdpa_alloc_device(struct eni_vdpa, vdpa,
-				     dev, &eni_vdpa_ops, 1, 1, NULL, false);
+				     dev, &eni_vdpa_ops, NULL,
+				     1, 1, NULL, false);
 	if (IS_ERR(eni_vdpa)) {
 		ENI_ERR(pdev, "failed to allocate vDPA structure\n");
 		return PTR_ERR(eni_vdpa);

drivers/vdpa/ifcvf/ifcvf_main.c

@@ -705,7 +705,8 @@ static int ifcvf_vdpa_dev_add(struct vdpa_mgmt_dev *mdev, const char *name,
 	vf = &ifcvf_mgmt_dev->vf;
 	pdev = vf->pdev;
 	adapter = vdpa_alloc_device(struct ifcvf_adapter, vdpa,
-				    &pdev->dev, &ifc_vdpa_ops, 1, 1, NULL, false);
+				    &pdev->dev, &ifc_vdpa_ops,
+				    NULL, 1, 1, NULL, false);
 	if (IS_ERR(adapter)) {
 		IFCVF_ERR(pdev, "Failed to allocate vDPA structure");
 		return PTR_ERR(adapter);

drivers/vdpa/mlx5/net/mlx5_vnet.c

@@ -3882,7 +3882,7 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name,
 	}
 
 	ndev = vdpa_alloc_device(struct mlx5_vdpa_net, mvdev.vdev, mdev->device, &mgtdev->vdpa_ops,
-				 MLX5_VDPA_NUMVQ_GROUPS, MLX5_VDPA_NUM_AS, name, false);
+				 NULL, MLX5_VDPA_NUMVQ_GROUPS, MLX5_VDPA_NUM_AS, name, false);
 	if (IS_ERR(ndev))
 		return PTR_ERR(ndev);
 

drivers/vdpa/octeon_ep/octep_vdpa_main.c

@@ -508,8 +508,8 @@ static int octep_vdpa_dev_add(struct vdpa_mgmt_dev *mdev, const char *name,
 	u64 device_features;
 	int ret;
 
-	oct_vdpa = vdpa_alloc_device(struct octep_vdpa, vdpa, &pdev->dev, &octep_vdpa_ops, 1, 1,
-				     NULL, false);
+	oct_vdpa = vdpa_alloc_device(struct octep_vdpa, vdpa, &pdev->dev, &octep_vdpa_ops,
+				     NULL, 1, 1, NULL, false);
 	if (IS_ERR(oct_vdpa)) {
 		dev_err(&pdev->dev, "Failed to allocate vDPA structure for octep vdpa device");
 		return PTR_ERR(oct_vdpa);

drivers/vdpa/pds/vdpa_dev.c

@@ -632,7 +632,8 @@ static int pds_vdpa_dev_add(struct vdpa_mgmt_dev *mdev, const char *name,
 	}
 
 	pdsv = vdpa_alloc_device(struct pds_vdpa_device, vdpa_dev,
-				 dev, &pds_vdpa_ops, 1, 1, name, false);
+				 dev, &pds_vdpa_ops, NULL,
+				 1, 1, name, false);
 	if (IS_ERR(pdsv)) {
 		dev_err(dev, "Failed to allocate vDPA structure: %pe\n", pdsv);
 		return PTR_ERR(pdsv);

drivers/vdpa/solidrun/snet_main.c

@@ -1008,8 +1008,8 @@ static int snet_vdpa_probe_vf(struct pci_dev *pdev)
 	}
 
 	/* Allocate vdpa device */
-	snet = vdpa_alloc_device(struct snet, vdpa, &pdev->dev, &snet_config_ops, 1, 1, NULL,
-				 false);
+	snet = vdpa_alloc_device(struct snet, vdpa, &pdev->dev, &snet_config_ops,
+				 NULL, 1, 1, NULL, false);
 	if (!snet) {
 		SNET_ERR(pdev, "Failed to allocate a vdpa device\n");
 		ret = -ENOMEM;

drivers/vdpa/vdpa.c

@@ -142,6 +142,7 @@ static void vdpa_release_dev(struct device *d)
  * initialized but before registered.
  * @parent: the parent device
  * @config: the bus operations that is supported by this device
+ * @map: the map operations that is supported by this device
  * @ngroups: number of groups supported by this device
  * @nas: number of address spaces supported by this device
  * @size: size of the parent structure that contains private data
@@ -156,6 +157,7 @@ static void vdpa_release_dev(struct device *d)
  */
 struct vdpa_device *__vdpa_alloc_device(struct device *parent,
 					const struct vdpa_config_ops *config,
+					const struct virtio_map_ops *map,
 					unsigned int ngroups, unsigned int nas,
 					size_t size, const char *name,
 					bool use_va)
@@ -187,6 +189,7 @@ struct vdpa_device *__vdpa_alloc_device(struct device *parent,
 	vdev->dev.release = vdpa_release_dev;
 	vdev->index = err;
 	vdev->config = config;
+	vdev->map = map;
 	vdev->features_valid = false;
 	vdev->use_va = use_va;
 	vdev->ngroups = ngroups;

drivers/vdpa/vdpa_sim/vdpa_sim.c

@@ -215,7 +215,7 @@ struct vdpasim *vdpasim_create(struct vdpasim_dev_attr *dev_attr,
 	else
 		ops = &vdpasim_config_ops;
 
-	vdpa = __vdpa_alloc_device(NULL, ops,
+	vdpa = __vdpa_alloc_device(NULL, ops, NULL,
 				   dev_attr->ngroups, dev_attr->nas,
 				   dev_attr->alloc_size,
 				   dev_attr->name, use_va);

drivers/vdpa/vdpa_user/vduse_dev.c

@@ -2009,7 +2009,8 @@ static int vduse_dev_init_vdpa(struct vduse_dev *dev, const char *name)
 		return -EEXIST;
 
 	vdev = vdpa_alloc_device(struct vduse_vdpa, vdpa, dev->dev,
-				 &vduse_vdpa_config_ops, 1, 1, name, true);
+				 &vduse_vdpa_config_ops, NULL,
+				 1, 1, name, true);
 	if (IS_ERR(vdev))
 		return PTR_ERR(vdev);
 

drivers/vdpa/virtio_pci/vp_vdpa.c

@@ -511,7 +511,8 @@ static int vp_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name,
 	int ret, i;
 
 	vp_vdpa = vdpa_alloc_device(struct vp_vdpa, vdpa,
-				    dev, &vp_vdpa_ops, 1, 1, name, false);
+				    dev, &vp_vdpa_ops, NULL,
+				    1, 1, name, false);
 
 	if (IS_ERR(vp_vdpa)) {
 		dev_err(dev, "vp_vdpa: Failed to allocate vDPA structure\n");

drivers/virtio/virtio_vdpa.c

@@ -466,9 +466,11 @@ static int virtio_vdpa_probe(struct vdpa_device *vdpa)
 	if (!vd_dev)
 		return -ENOMEM;
 
-	vd_dev->vdev.dev.parent = vdpa_get_map(vdpa).dma_dev;
+	vd_dev->vdev.dev.parent = vdpa->map ? &vdpa->dev :
+				  vdpa_get_map(vdpa).dma_dev;
 	vd_dev->vdev.dev.release = virtio_vdpa_release_dev;
 	vd_dev->vdev.config = &virtio_vdpa_config_ops;
+	vd_dev->vdev.map = vdpa->map;
 	vd_dev->vdpa = vdpa;
 
 	vd_dev->vdev.id.device = ops->get_device_id(vdpa);

include/linux/vdpa.h

@@ -76,6 +76,7 @@ struct vdpa_mgmt_dev;
  *                   because core frees it; use driver_set_override() to
  *                   set or clear it.
  * @config: the configuration ops for this device.
+ * @map: the map ops for this device
  * @cf_lock: Protects get and set access to configuration layout.
  * @index: device index
  * @features_valid: were features initialized? for legacy guests
@@ -91,6 +92,7 @@ struct vdpa_device {
 	union virtio_map vmap;
 	const char *driver_override;
 	const struct vdpa_config_ops *config;
+	const struct virtio_map_ops *map;
 	struct rw_semaphore cf_lock; /* Protects get/set config */
 	unsigned int index;
 	bool features_valid;
@@ -447,6 +449,7 @@ struct vdpa_config_ops {
 
 struct vdpa_device *__vdpa_alloc_device(struct device *parent,
 					const struct vdpa_config_ops *config,
+					const struct virtio_map_ops *map,
 					unsigned int ngroups, unsigned int nas,
 					size_t size, const char *name,
 					bool use_va);
@@ -458,6 +461,7 @@ struct vdpa_device *__vdpa_alloc_device(struct device *parent,
  * @member: the name of struct vdpa_device within the @dev_struct
  * @parent: the parent device
  * @config: the bus operations that is supported by this device
+ * @map: the map operations that is supported by this device
  * @ngroups: the number of virtqueue groups supported by this device
  * @nas: the number of address spaces
  * @name: name of the vdpa device
@@ -465,10 +469,10 @@ struct vdpa_device *__vdpa_alloc_device(struct device *parent,
  *
  * Return allocated data structure or ERR_PTR upon error
  */
-#define vdpa_alloc_device(dev_struct, member, parent, config, ngroups, nas, \
-			  name, use_va) \
+#define vdpa_alloc_device(dev_struct, member, parent, config, map, \
+			  ngroups, nas, name, use_va)		   \
 			  container_of((__vdpa_alloc_device( \
-				       parent, config, ngroups, nas, \
+				       parent, config, map, ngroups, nas, \
 				       (sizeof(dev_struct) + \
 				       BUILD_BUG_ON_ZERO(offsetof( \
 				       dev_struct, member))), name, use_va)), \