[PATCH v5 2/9] mshv: Add declarations and definitions for VFIO-MSHV bridge device

Mukesh R <[email protected]> Fri, 31 Jul 2026 15:34:20 -0700
Newsgroups dev.linux.lists.iommu,org.kernel.vger.linux-arch,org.kernel.vger.linux-hyperv,org.kernel.vger.linux-kernel,org.kernel.vger.linux-pci
Message-ID <[email protected]>
Add data structs needed by the subsequent patch that introduces a new
module to implement VFIO-MSHV pseudo device.

Signed-off-by: Mukesh R <[email protected]>
Reviewed-by: Souradeep Chakrabarti <[email protected]>
---
 drivers/hv/mshv_root.h    | 19 +++++++++++++++++++
 include/uapi/linux/mshv.h | 30 ++++++++++++++++++++++++++++++
 2 files changed, 49 insertions(+)

diff --git a/drivers/hv/mshv_root.h b/drivers/hv/mshv_root.h
index a85c24dcc701..43114df3cbf0 100644
--- a/drivers/hv/mshv_root.h
+++ b/drivers/hv/mshv_root.h
@@ -227,6 +227,25 @@ struct port_table_info {
 	};
 };
 
+struct mshv_device {
+	const struct mshv_device_ops *device_ops;
+	struct mshv_partition *device_pt;
+	void *device_private;
+	struct hlist_node device_ptnode;
+};
+
+struct mshv_device_ops {
+	const char *device_name;
+	long (*device_create)(struct mshv_device *dev);
+	void (*device_release)(struct mshv_device *dev);
+	long (*device_set_attr)(struct mshv_device *dev,
+				struct mshv_device_attr *attr);
+	long (*device_has_attr)(struct mshv_device *dev,
+				struct mshv_device_attr *attr);
+};
+
+extern const struct mshv_device_ops mshv_vfio_device_ops;
+
 int mshv_update_routing_table(struct mshv_partition *partition,
 			      const struct mshv_user_irq_entry *entries,
 			      unsigned int numents);
diff --git a/include/uapi/linux/mshv.h b/include/uapi/linux/mshv.h
index 32ff92b6342b..be6fe3ee8707 100644
--- a/include/uapi/linux/mshv.h
+++ b/include/uapi/linux/mshv.h
@@ -404,4 +404,34 @@ struct mshv_sint_mask {
 /* hv_hvcall device */
 #define MSHV_HVCALL_SETUP        _IOW(MSHV_IOCTL, 0x1E, struct mshv_vtl_hvcall_setup)
 #define MSHV_HVCALL              _IOWR(MSHV_IOCTL, 0x1F, struct mshv_vtl_hvcall)
+
+/* Device passhthru */
+#define MSHV_CREATE_DEVICE_TEST		1
+
+enum {
+	MSHV_DEV_TYPE_VFIO,
+	MSHV_DEV_TYPE_MAX,
+};
+
+struct mshv_create_device {
+	__u32	type;	     /* in: MSHV_DEV_TYPE_xxx */
+	__u32	fd;	     /* out: device handle */
+	__u32	flags;	     /* in: MSHV_CREATE_DEVICE_xxx */
+};
+
+#define MSHV_DEV_VFIO_FILE      1
+#define MSHV_DEV_VFIO_FILE_ADD	1
+#define MSHV_DEV_VFIO_FILE_DEL	2
+
+struct mshv_device_attr {
+	__u32	flags;		/* no flags currently defined */
+	__u32	group;		/* device-defined */
+	__u64	attr;		/* group-defined */
+	__u64	addr;		/* userspace address of attr data */
+};
+
+/* Device fds created with MSHV_CREATE_DEVICE */
+#define MSHV_SET_DEVICE_ATTR	_IOW(MSHV_IOCTL, 0x00, struct mshv_device_attr)
+#define MSHV_HAS_DEVICE_ATTR	_IOW(MSHV_IOCTL, 0x01, struct mshv_device_attr)
+
 #endif
-- 
2.51.2.vfs.0.1