Drivers: hv: VMBus protocol version 6.0

The confidential VMBus is supported starting from the protocol
version 6.0 onwards.

Provide the required definitions. No functional changes.

Signed-off-by: Roman Kisel <[e-mail]>
Reviewed-by: Alok Tiwari <[e-mail]>
Reviewed-by: Michael Kelley <[e-mail]>
Signed-off-by: Wei Liu <[e-mail]>

drivers/hv/hyperv_vmbus.h

···
 
 /* General vmbus interface */
 
+bool vmbus_is_confidential(void);
+
 struct hv_device *vmbus_device_create(const guid_t *type,
 				      const guid_t *instance,
 				      struct vmbus_channel *channel);

drivers/hv/vmbus_drv.c

···
 int vmbus_interrupt;
 
 /*
+ * If the Confidential VMBus is used, the data on the "wire" is not
+ * visible to either the host or the hypervisor.
+ */
+static bool is_confidential;
+
+bool vmbus_is_confidential(void)
+{
+	return is_confidential;
+}
+EXPORT_SYMBOL_GPL(vmbus_is_confidential);
+
+/*
  * The panic notifier below is responsible solely for unloading the
  * vmbus connection, which is necessary in a panic event.
  *

include/hyperv/hvgdk_mini.h

···
 #define HYPERV_CPUID_VIRT_STACK_PROPERTIES	 0x40000082
 /* Support for the extended IOAPIC RTE format */
 #define HYPERV_VS_PROPERTIES_EAX_EXTENDED_IOAPIC_RTE	 BIT(2)
+#define HYPERV_VS_PROPERTIES_EAX_CONFIDENTIAL_VMBUS_AVAILABLE	 BIT(3)
 
 #define HYPERV_HYPERVISOR_PRESENT_BIT		 0x80000000
 #define HYPERV_CPUID_MIN			 0x40000005

include/linux/hyperv.h

···
  * Linux kernel.
  */
 
-#define VERSION_WS2008  ((0 << 16) | (13))
-#define VERSION_WIN7    ((1 << 16) | (1))
-#define VERSION_WIN8    ((2 << 16) | (4))
-#define VERSION_WIN8_1    ((3 << 16) | (0))
-#define VERSION_WIN10 ((4 << 16) | (0))
-#define VERSION_WIN10_V4_1 ((4 << 16) | (1))
-#define VERSION_WIN10_V5 ((5 << 16) | (0))
-#define VERSION_WIN10_V5_1 ((5 << 16) | (1))
-#define VERSION_WIN10_V5_2 ((5 << 16) | (2))
-#define VERSION_WIN10_V5_3 ((5 << 16) | (3))
+#define VMBUS_MAKE_VERSION(MAJ, MIN)	((((u32)MAJ) << 16) | (MIN))
+#define VERSION_WS2008					VMBUS_MAKE_VERSION(0, 13)
+#define VERSION_WIN7					VMBUS_MAKE_VERSION(1, 1)
+#define VERSION_WIN8					VMBUS_MAKE_VERSION(2, 4)
+#define VERSION_WIN8_1					VMBUS_MAKE_VERSION(3, 0)
+#define VERSION_WIN10					VMBUS_MAKE_VERSION(4, 0)
+#define VERSION_WIN10_V4_1				VMBUS_MAKE_VERSION(4, 1)
+#define VERSION_WIN10_V5				VMBUS_MAKE_VERSION(5, 0)
+#define VERSION_WIN10_V5_1				VMBUS_MAKE_VERSION(5, 1)
+#define VERSION_WIN10_V5_2				VMBUS_MAKE_VERSION(5, 2)
+#define VERSION_WIN10_V5_3				VMBUS_MAKE_VERSION(5, 3)
+#define VERSION_WIN10_V6_0				VMBUS_MAKE_VERSION(6, 0)
 
 /* Make maximum size of pipe payload of 16K */
 #define MAX_PIPE_DATA_PAYLOAD		(sizeof(u8) * 16384)
···
 } __packed;
 
 /* Server Flags */
-#define VMBUS_CHANNEL_ENUMERATE_DEVICE_INTERFACE	1
-#define VMBUS_CHANNEL_SERVER_SUPPORTS_TRANSFER_PAGES	2
-#define VMBUS_CHANNEL_SERVER_SUPPORTS_GPADLS		4
-#define VMBUS_CHANNEL_NAMED_PIPE_MODE			0x10
-#define VMBUS_CHANNEL_LOOPBACK_OFFER			0x100
-#define VMBUS_CHANNEL_PARENT_OFFER			0x200
-#define VMBUS_CHANNEL_REQUEST_MONITORED_NOTIFICATION	0x400
-#define VMBUS_CHANNEL_TLNPI_PROVIDER_OFFER		0x2000
+#define VMBUS_CHANNEL_ENUMERATE_DEVICE_INTERFACE		0x0001
+/*
+ * This flag indicates that the channel is offered by the paravisor, and must
+ * use encrypted memory for the channel ring buffer.
+ */
+#define VMBUS_CHANNEL_CONFIDENTIAL_RING_BUFFER			0x0002
+/*
+ * This flag indicates that the channel is offered by the paravisor, and must
+ * use encrypted memory for GPA direct packets and additional GPADLs.
+ */
+#define VMBUS_CHANNEL_CONFIDENTIAL_EXTERNAL_MEMORY		0x0004
+#define VMBUS_CHANNEL_NAMED_PIPE_MODE					0x0010
+#define VMBUS_CHANNEL_LOOPBACK_OFFER					0x0100
+#define VMBUS_CHANNEL_PARENT_OFFER						0x0200
+#define VMBUS_CHANNEL_REQUEST_MONITORED_NOTIFICATION	0x0400
+#define VMBUS_CHANNEL_TLNPI_PROVIDER_OFFER				0x2000
 
 struct vmpacket_descriptor {
 	u16 type;
···
 	u32 child_relid;
 } __packed;
 
+/*
+ * Used by the paravisor only, means that the encrypted ring buffers and
+ * the encrypted external memory are supported
+ */
+#define VMBUS_FEATURE_FLAG_CONFIDENTIAL_CHANNELS	0x10
+
 struct vmbus_channel_initiate_contact {
 	struct vmbus_channel_message_header header;
 	u32 vmbus_version_requested;
···
 		struct {
 			u8	msg_sint;
 			u8	msg_vtl;
-			u8	reserved[6];
+			u8	reserved[2];
+			u32 feature_flags; /* VMBus version 6.0 */
 		};
 	};
 	u64 monitor_page1;
···
 
 	/* boolean to control visibility of sysfs for ring buffer */
 	bool ring_sysfs_visible;
+	/* The ring buffer is encrypted */
+	bool co_ring_buffer;
+	/* The external memory is encrypted */
+	bool co_external_memory;
 };
 
 #define lock_requestor(channel, flags)					\
···
 u64 vmbus_request_addr_match(struct vmbus_channel *channel, u64 trans_id,
 			     u64 rqst_addr);
 u64 vmbus_request_addr(struct vmbus_channel *channel, u64 trans_id);
+
+static inline bool is_co_ring_buffer(const struct vmbus_channel_offer_channel *o)
+{
+	return !!(o->offer.chn_flags & VMBUS_CHANNEL_CONFIDENTIAL_RING_BUFFER);
+}
+
+static inline bool is_co_external_memory(const struct vmbus_channel_offer_channel *o)
+{
+	return !!(o->offer.chn_flags & VMBUS_CHANNEL_CONFIDENTIAL_EXTERNAL_MEMORY);
+}
 
 static inline bool is_hvsock_offer(const struct vmbus_channel_offer_channel *o)
 {