RE: [EXTERNAL] Re: [PATCH v4 2/5] x86/hyperv: Add VTL specific structs and hypercalls

[Saurabh Singh Sengar <ssengar@microsoft.com>]

> -----Original Message-----
> From: Saurabh Singh Sengar <ssengar@linux.microsoft.com>
> Sent: Saturday, April 8, 2023 9:58 AM
> To: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>
> Cc: tglx@linutronix.de; mingo@redhat.com; bp@alien8.de;
> dave.hansen@linux.intel.com; x86@kernel.org; hpa@zytor.com; KY
> Srinivasan <kys@microsoft.com>; Haiyang Zhang
> <haiyangz@microsoft.com>; wei.liu@kernel.org; Dexuan Cui
> <decui@microsoft.com>; arnd@arndb.de; Tianyu Lan
> <Tianyu.Lan@microsoft.com>; Michael Kelley (LINUX)
> <mikelley@microsoft.com>; linux-kernel@vger.kernel.org; linux-
> hyperv@vger.kernel.org; linux-arch@vger.kernel.org; jgross@suse.com;
> mat.jonczyk@o2.pl
> Subject: [EXTERNAL] Re: [PATCH v4 2/5] x86/hyperv: Add VTL specific structs
> and hypercalls
> 
> On Thu, Apr 06, 2023 at 06:51:13AM -0700, Stanislav Kinsburskii wrote:
> > On Tue, Apr 04, 2023 at 02:01:01AM -0700, Saurabh Sengar wrote:
> > > Add structs and hypercalls required to enable VTL support on x86.
> > >
> > > Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
> > > Reviewed-by: Michael Kelley <mikelley@microsoft.com>
> > > ---
> > >  arch/x86/include/asm/hyperv-tlfs.h | 75
> > > ++++++++++++++++++++++++++++++  include/asm-generic/hyperv-tlfs.h  |
> > > 4 ++
> > >  2 files changed, 79 insertions(+)
> > >
> > > diff --git a/arch/x86/include/asm/hyperv-tlfs.h
> > > b/arch/x86/include/asm/hyperv-tlfs.h
> > > index 0b73a809e9e1..0b0b4e9a4318 100644
> > > --- a/arch/x86/include/asm/hyperv-tlfs.h
> > > +++ b/arch/x86/include/asm/hyperv-tlfs.h
> > > @@ -713,6 +713,81 @@ union hv_msi_entry {
> > >  	} __packed;
> > >  };
> > >
> > > +struct hv_x64_segment_register {
> > > +	__u64 base;
> >
> > Ideally they arch-size types naming should be consistent: either with
> > underscores or without.
> > The majority of cases in this file are without underscores.
> 
> Although I am fine either way, I think in a non-uapi file "without underscore"
> is prefered.
> I can change this in next version.

After reconsidering, I believe it would be wise to consult the "x86 maintainers" regarding this matter.
Hence, I intend to send the next version without this change.

- Saurabh

> 
> Regards,
> Saurabh
> 
> 
> >
> > Reviewed-by: Stanislav Kinsburskii <stanislav.kinsburskii@gmail.com>
> >
> > > +	__u32 limit;
> > > +	__u16 selector;
> > > +	union {
> > > +		struct {
> > > +			__u16 segment_type : 4;
> > > +			__u16 non_system_segment : 1;
> > > +			__u16 descriptor_privilege_level : 2;
> > > +			__u16 present : 1;
> > > +			__u16 reserved : 4;
> > > +			__u16 available : 1;
> > > +			__u16 _long : 1;
> > > +			__u16 _default : 1;
> > > +			__u16 granularity : 1;
> > > +		} __packed;
> > > +		__u16 attributes;
> > > +	};
> > > +} __packed;
> > > +
> > > +struct hv_x64_table_register {
> > > +	__u16 pad[3];
> > > +	__u16 limit;
> > > +	__u64 base;
> > > +} __packed;
> > > +
> > > +struct hv_init_vp_context {
> > > +	u64 rip;
> > > +	u64 rsp;
> > > +	u64 rflags;
> > > +
> > > +	struct hv_x64_segment_register cs;
> > > +	struct hv_x64_segment_register ds;
> > > +	struct hv_x64_segment_register es;
> > > +	struct hv_x64_segment_register fs;
> > > +	struct hv_x64_segment_register gs;
> > > +	struct hv_x64_segment_register ss;
> > > +	struct hv_x64_segment_register tr;
> > > +	struct hv_x64_segment_register ldtr;
> > > +
> > > +	struct hv_x64_table_register idtr;
> > > +	struct hv_x64_table_register gdtr;
> > > +
> > > +	u64 efer;
> > > +	u64 cr0;
> > > +	u64 cr3;
> > > +	u64 cr4;
> > > +	u64 msr_cr_pat;
> > > +} __packed;
> > > +
> > > +union hv_input_vtl {
> > > +	u8 as_uint8;
> > > +	struct {
> > > +		u8 target_vtl: 4;
> > > +		u8 use_target_vtl: 1;
> > > +		u8 reserved_z: 3;
> > > +	};
> > > +} __packed;
> > > +
> > > +struct hv_enable_vp_vtl {
> > > +	u64				partition_id;
> > > +	u32				vp_index;
> > > +	union hv_input_vtl		target_vtl;
> > > +	u8				mbz0;
> > > +	u16				mbz1;
> > > +	struct hv_init_vp_context	vp_context;
> > > +} __packed;
> > > +
> > > +struct hv_get_vp_from_apic_id_in {
> > > +	u64 partition_id;
> > > +	union hv_input_vtl target_vtl;
> > > +	u8 res[7];
> > > +	u32 apic_ids[];
> > > +} __packed;
> > > +
> > >  #include <asm-generic/hyperv-tlfs.h>
> > >
> > >  #endif
> > > diff --git a/include/asm-generic/hyperv-tlfs.h
> > > b/include/asm-generic/hyperv-tlfs.h
> > > index b870983596b9..87258341fd7c 100644
> > > --- a/include/asm-generic/hyperv-tlfs.h
> > > +++ b/include/asm-generic/hyperv-tlfs.h
> > > @@ -146,6 +146,7 @@ union hv_reference_tsc_msr {
> > >  /* Declare the various hypercall operations. */
> > >  #define HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE	0x0002
> > >  #define HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST	0x0003
> > > +#define HVCALL_ENABLE_VP_VTL			0x000f
> > >  #define HVCALL_NOTIFY_LONG_SPIN_WAIT		0x0008
> > >  #define HVCALL_SEND_IPI				0x000b
> > >  #define HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX	0x0013
> > > @@ -165,6 +166,8 @@ union hv_reference_tsc_msr {
> > >  #define HVCALL_MAP_DEVICE_INTERRUPT		0x007c
> > >  #define HVCALL_UNMAP_DEVICE_INTERRUPT		0x007d
> > >  #define HVCALL_RETARGET_INTERRUPT		0x007e
> > > +#define HVCALL_START_VP				0x0099
> > > +#define HVCALL_GET_VP_ID_FROM_APIC_ID		0x009a
> > >  #define HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_SPACE 0x00af
> #define
> > > HVCALL_FLUSH_GUEST_PHYSICAL_ADDRESS_LIST 0x00b0  #define
> > > HVCALL_MODIFY_SPARSE_GPA_PAGE_HOST_VISIBILITY 0x00db @@ -
> 218,6
> > > +221,7 @@ enum HV_GENERIC_SET_FORMAT {
> > >  #define HV_STATUS_INVALID_PORT_ID		17
> > >  #define HV_STATUS_INVALID_CONNECTION_ID		18
> > >  #define HV_STATUS_INSUFFICIENT_BUFFERS		19
> > > +#define HV_STATUS_VTL_ALREADY_ENABLED		134
> > >
> > >  /*
> > >   * The Hyper-V TimeRefCount register and the TSC
> > > --
> > > 2.34.1