From: Roman Kisel <[email protected]> Sent: Monday, July 14, 2025 3:16 PM > > The confidential VMBus is supported starting from the protocol > version 6.0 onwards. > > Update the relevant definitions, and provide a function that returns > whether VMBus is confidential or not. No functional changes. > > Signed-off-by: Roman Kisel <[email protected]> > Reviewed-by: Alok Tiwari <[email protected]>
Reviewed-by: Michael Kelley <[email protected]> > --- > drivers/hv/vmbus_drv.c | 12 ++++++ > include/asm-generic/mshyperv.h | 1 + > include/linux/hyperv.h | 69 ++++++++++++++++++++++++---------- > 3 files changed, 63 insertions(+), 19 deletions(-) > > diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c > index 33b524b4eb5e..698c86c4ef03 100644 > --- a/drivers/hv/vmbus_drv.c > +++ b/drivers/hv/vmbus_drv.c > @@ -56,6 +56,18 @@ static long __percpu *vmbus_evt; > int vmbus_irq; > 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. > diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h > index a729b77983fa..9722934a8332 100644 > --- a/include/asm-generic/mshyperv.h > +++ b/include/asm-generic/mshyperv.h > @@ -373,6 +373,7 @@ static inline int hv_call_create_vp(int node, u64 > partition_id, u32 vp_index, u3 > return -EOPNOTSUPP; > } > #endif /* CONFIG_MSHV_ROOT */ > +bool vmbus_is_confidential(void); > > #if IS_ENABLED(CONFIG_HYPERV_VTL_MODE) > u8 __init get_vtl(void); > diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h > index a59c5c3e95fb..a1820fabbfc0 100644 > --- a/include/linux/hyperv.h > +++ b/include/linux/hyperv.h > @@ -265,16 +265,18 @@ static inline u32 hv_get_avail_to_write_percent( > * 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) > @@ -335,14 +337,22 @@ struct vmbus_channel_offer { > } __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; > @@ -621,6 +631,12 @@ struct vmbus_channel_relid_released { > 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; > @@ -630,7 +646,8 @@ struct vmbus_channel_initiate_contact { > struct { > u8 msg_sint; > u8 msg_vtl; > - u8 reserved[6]; > + u8 reserved[2]; > + u32 feature_flags; /* VMBus version 6.0 */ > }; > }; > u64 monitor_page1; > @@ -1008,6 +1025,10 @@ struct vmbus_channel { > > /* 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) > \ > @@ -1032,6 +1053,16 @@ 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) > { > return !!(o->offer.chn_flags & VMBUS_CHANNEL_TLNPI_PROVIDER_OFFER); > -- > 2.43.0
