diff mbox series

[v19,109/130] KVM: TDX: Handle TDX PV port io hypercall

Message ID 4f4aaf292008608a8717e9553c3315ee02f66b20.1708933498.git.isaku.yamahata@intel.com (mailing list archive)
State New, archived
Headers show
Series [v19,001/130] x86/virt/tdx: Rename _offset to _member for TD_SYSINFO_MAP() macro | expand

Commit Message

Isaku Yamahata Feb. 26, 2024, 8:26 a.m. UTC
From: Isaku Yamahata <isaku.yamahata@intel.com>

Wire up TDX PV port IO hypercall to the KVM backend function.

Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
---
v18:
- Fix out case to set R10 and R11 correctly when user space handled port
  out.
---
 arch/x86/kvm/vmx/tdx.c | 67 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 67 insertions(+)

Comments

Binbin Wu April 17, 2024, 12:51 p.m. UTC | #1
On 2/26/2024 4:26 PM, isaku.yamahata@intel.com wrote:
> From: Isaku Yamahata <isaku.yamahata@intel.com>
>
> Wire up TDX PV port IO hypercall to the KVM backend function.
>
> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
> v18:
> - Fix out case to set R10 and R11 correctly when user space handled port
>    out.
> ---
>   arch/x86/kvm/vmx/tdx.c | 67 ++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 67 insertions(+)
>
> diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> index a2caf2ae838c..55fc6cc6c816 100644
> --- a/arch/x86/kvm/vmx/tdx.c
> +++ b/arch/x86/kvm/vmx/tdx.c
> @@ -1152,6 +1152,71 @@ static int tdx_emulate_hlt(struct kvm_vcpu *vcpu)
>   	return kvm_emulate_halt_noskip(vcpu);
>   }
>   
> +static int tdx_complete_pio_out(struct kvm_vcpu *vcpu)
> +{
> +	tdvmcall_set_return_code(vcpu, TDVMCALL_SUCCESS);
> +	tdvmcall_set_return_val(vcpu, 0);
> +	return 1;
> +}
> +
> +static int tdx_complete_pio_in(struct kvm_vcpu *vcpu)
> +{
> +	struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
> +	unsigned long val = 0;
> +	int ret;
> +
> +	WARN_ON_ONCE(vcpu->arch.pio.count != 1);
> +
> +	ret = ctxt->ops->pio_in_emulated(ctxt, vcpu->arch.pio.size,
> +					 vcpu->arch.pio.port, &val, 1);
> +	WARN_ON_ONCE(!ret);
> +
> +	tdvmcall_set_return_code(vcpu, TDVMCALL_SUCCESS);
> +	tdvmcall_set_return_val(vcpu, val);
> +
> +	return 1;
> +}
> +
> +static int tdx_emulate_io(struct kvm_vcpu *vcpu)
> +{
> +	struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
> +	unsigned long val = 0;
> +	unsigned int port;
> +	int size, ret;
> +	bool write;
> +
> +	++vcpu->stat.io_exits;
> +
> +	size = tdvmcall_a0_read(vcpu);
> +	write = tdvmcall_a1_read(vcpu);
> +	port = tdvmcall_a2_read(vcpu);
> +
> +	if (size != 1 && size != 2 && size != 4) {
> +		tdvmcall_set_return_code(vcpu, TDVMCALL_INVALID_OPERAND);
> +		return 1;
> +	}
> +
> +	if (write) {
> +		val = tdvmcall_a3_read(vcpu);
> +		ret = ctxt->ops->pio_out_emulated(ctxt, size, port, &val, 1);
> +
> +		/* No need for a complete_userspace_io callback. */
I am confused about the comment.

The code below sets the complete_userspace_io callback for write case,
i.e. tdx_complete_pio_out().

> +		vcpu->arch.pio.count = 0;
> +	} else
> +		ret = ctxt->ops->pio_in_emulated(ctxt, size, port, &val, 1);
> +
> +	if (ret)
> +		tdvmcall_set_return_val(vcpu, val);
> +	else {
> +		if (write)
> +			vcpu->arch.complete_userspace_io = tdx_complete_pio_out;
> +		else
> +			vcpu->arch.complete_userspace_io = tdx_complete_pio_in;
> +	}
> +
> +	return ret;
> +}
> +
>   static int handle_tdvmcall(struct kvm_vcpu *vcpu)
>   {
>   	if (tdvmcall_exit_type(vcpu))
> @@ -1162,6 +1227,8 @@ static int handle_tdvmcall(struct kvm_vcpu *vcpu)
>   		return tdx_emulate_cpuid(vcpu);
>   	case EXIT_REASON_HLT:
>   		return tdx_emulate_hlt(vcpu);
> +	case EXIT_REASON_IO_INSTRUCTION:
> +		return tdx_emulate_io(vcpu);
>   	default:
>   		break;
>   	}
Isaku Yamahata April 17, 2024, 8:10 p.m. UTC | #2
On Wed, Apr 17, 2024 at 08:51:39PM +0800,
Binbin Wu <binbin.wu@linux.intel.com> wrote:

> 
> 
> On 2/26/2024 4:26 PM, isaku.yamahata@intel.com wrote:
> > From: Isaku Yamahata <isaku.yamahata@intel.com>
> > 
> > Wire up TDX PV port IO hypercall to the KVM backend function.
> > 
> > Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
> > Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
> > ---
> > v18:
> > - Fix out case to set R10 and R11 correctly when user space handled port
> >    out.
> > ---
> >   arch/x86/kvm/vmx/tdx.c | 67 ++++++++++++++++++++++++++++++++++++++++++
> >   1 file changed, 67 insertions(+)
> > 
> > diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> > index a2caf2ae838c..55fc6cc6c816 100644
> > --- a/arch/x86/kvm/vmx/tdx.c
> > +++ b/arch/x86/kvm/vmx/tdx.c
> > @@ -1152,6 +1152,71 @@ static int tdx_emulate_hlt(struct kvm_vcpu *vcpu)
> >   	return kvm_emulate_halt_noskip(vcpu);
> >   }
> > +static int tdx_complete_pio_out(struct kvm_vcpu *vcpu)
> > +{
> > +	tdvmcall_set_return_code(vcpu, TDVMCALL_SUCCESS);
> > +	tdvmcall_set_return_val(vcpu, 0);
> > +	return 1;
> > +}
> > +
> > +static int tdx_complete_pio_in(struct kvm_vcpu *vcpu)
> > +{
> > +	struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
> > +	unsigned long val = 0;
> > +	int ret;
> > +
> > +	WARN_ON_ONCE(vcpu->arch.pio.count != 1);
> > +
> > +	ret = ctxt->ops->pio_in_emulated(ctxt, vcpu->arch.pio.size,
> > +					 vcpu->arch.pio.port, &val, 1);
> > +	WARN_ON_ONCE(!ret);
> > +
> > +	tdvmcall_set_return_code(vcpu, TDVMCALL_SUCCESS);
> > +	tdvmcall_set_return_val(vcpu, val);
> > +
> > +	return 1;
> > +}
> > +
> > +static int tdx_emulate_io(struct kvm_vcpu *vcpu)
> > +{
> > +	struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
> > +	unsigned long val = 0;
> > +	unsigned int port;
> > +	int size, ret;
> > +	bool write;
> > +
> > +	++vcpu->stat.io_exits;
> > +
> > +	size = tdvmcall_a0_read(vcpu);
> > +	write = tdvmcall_a1_read(vcpu);
> > +	port = tdvmcall_a2_read(vcpu);
> > +
> > +	if (size != 1 && size != 2 && size != 4) {
> > +		tdvmcall_set_return_code(vcpu, TDVMCALL_INVALID_OPERAND);
> > +		return 1;
> > +	}
> > +
> > +	if (write) {
> > +		val = tdvmcall_a3_read(vcpu);
> > +		ret = ctxt->ops->pio_out_emulated(ctxt, size, port, &val, 1);
> > +
> > +		/* No need for a complete_userspace_io callback. */
> I am confused about the comment.
> 
> The code below sets the complete_userspace_io callback for write case,
> i.e. tdx_complete_pio_out().

You're correct. This comment is stale and should be removed it.
Binbin Wu July 9, 2024, 6:26 a.m. UTC | #3
On 4/18/2024 4:10 AM, Isaku Yamahata wrote:
> On Wed, Apr 17, 2024 at 08:51:39PM +0800,
> Binbin Wu <binbin.wu@linux.intel.com> wrote:
>
>>
>> On 2/26/2024 4:26 PM, isaku.yamahata@intel.com wrote:
>>> From: Isaku Yamahata <isaku.yamahata@intel.com>
>>>
>>> Wire up TDX PV port IO hypercall to the KVM backend function.
>>>
>>> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
>>> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
>>> ---
>>> v18:
>>> - Fix out case to set R10 and R11 correctly when user space handled port
>>>     out.
>>> ---
>>>    arch/x86/kvm/vmx/tdx.c | 67 ++++++++++++++++++++++++++++++++++++++++++
>>>    1 file changed, 67 insertions(+)
>>>
>>> diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
>>> index a2caf2ae838c..55fc6cc6c816 100644
>>> --- a/arch/x86/kvm/vmx/tdx.c
>>> +++ b/arch/x86/kvm/vmx/tdx.c
>>> @@ -1152,6 +1152,71 @@ static int tdx_emulate_hlt(struct kvm_vcpu *vcpu)
>>>    	return kvm_emulate_halt_noskip(vcpu);
>>>    }
>>> +static int tdx_complete_pio_out(struct kvm_vcpu *vcpu)
>>> +{
>>> +	tdvmcall_set_return_code(vcpu, TDVMCALL_SUCCESS);
>>> +	tdvmcall_set_return_val(vcpu, 0);
>>> +	return 1;
>>> +}
>>> +
>>> +static int tdx_complete_pio_in(struct kvm_vcpu *vcpu)
>>> +{
>>> +	struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
>>> +	unsigned long val = 0;
>>> +	int ret;
>>> +
>>> +	WARN_ON_ONCE(vcpu->arch.pio.count != 1);
>>> +
>>> +	ret = ctxt->ops->pio_in_emulated(ctxt, vcpu->arch.pio.size,
>>> +					 vcpu->arch.pio.port, &val, 1);
>>> +	WARN_ON_ONCE(!ret);
>>> +
>>> +	tdvmcall_set_return_code(vcpu, TDVMCALL_SUCCESS);
>>> +	tdvmcall_set_return_val(vcpu, val);
>>> +
>>> +	return 1;
>>> +}
>>> +
>>> +static int tdx_emulate_io(struct kvm_vcpu *vcpu)
>>> +{
>>> +	struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
>>> +	unsigned long val = 0;
>>> +	unsigned int port;
>>> +	int size, ret;
>>> +	bool write;
>>> +
>>> +	++vcpu->stat.io_exits;
>>> +
>>> +	size = tdvmcall_a0_read(vcpu);
>>> +	write = tdvmcall_a1_read(vcpu);
>>> +	port = tdvmcall_a2_read(vcpu);
>>> +
>>> +	if (size != 1 && size != 2 && size != 4) {
>>> +		tdvmcall_set_return_code(vcpu, TDVMCALL_INVALID_OPERAND);
>>> +		return 1;
>>> +	}
>>> +
>>> +	if (write) {
>>> +		val = tdvmcall_a3_read(vcpu);
>>> +		ret = ctxt->ops->pio_out_emulated(ctxt, size, port, &val, 1);
>>> +
>>> +		/* No need for a complete_userspace_io callback. */
>> I am confused about the comment.
>>
>> The code below sets the complete_userspace_io callback for write case,
>> i.e. tdx_complete_pio_out().
> You're correct. This comment is stale and should be removed it.
Also, since the tdx_complete_pio_out() is installed as 
complete_userspace_io callback for write, it's more reasonable to move 
the reset of pio.count into tdx_complete_pio_out().
How about the following fixup:

diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 9ead46cb75ab..b43bb8ccddb9 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -1115,6 +1115,7 @@ static int tdx_emulate_hlt(struct kvm_vcpu *vcpu)

  static int tdx_complete_pio_out(struct kvm_vcpu *vcpu)
  {
+       vcpu->arch.pio.count = 0;
         tdvmcall_set_return_code(vcpu, TDVMCALL_SUCCESS);
         tdvmcall_set_return_val(vcpu, 0);
         return 1;
@@ -1159,15 +1160,13 @@ static int tdx_emulate_io(struct kvm_vcpu *vcpu)
         if (write) {
                 val = tdvmcall_a3_read(vcpu);
                 ret = ctxt->ops->pio_out_emulated(ctxt, size, port, 
&val, 1);
-
-               /* No need for a complete_userspace_io callback. */
-               vcpu->arch.pio.count = 0;
-       } else
+       } else {
                 ret = ctxt->ops->pio_in_emulated(ctxt, size, port, 
&val, 1);
+       }

-       if (ret)
+       if (ret) {
                 tdvmcall_set_return_val(vcpu, val);
-       else {
+       } else {
                 if (write)
                         vcpu->arch.complete_userspace_io = 
tdx_complete_pio_out;
                 else
Isaku Yamahata July 16, 2024, 9:19 p.m. UTC | #4
On Tue, Jul 09, 2024 at 02:26:35PM +0800,
Binbin Wu <binbin.wu@linux.intel.com> wrote:

> 
> 
> On 4/18/2024 4:10 AM, Isaku Yamahata wrote:
> > On Wed, Apr 17, 2024 at 08:51:39PM +0800,
> > Binbin Wu <binbin.wu@linux.intel.com> wrote:
> > 
> > > 
> > > On 2/26/2024 4:26 PM, isaku.yamahata@intel.com wrote:
> > > > From: Isaku Yamahata <isaku.yamahata@intel.com>
> > > > 
> > > > Wire up TDX PV port IO hypercall to the KVM backend function.
> > > > 
> > > > Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
> > > > Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
> > > > ---
> > > > v18:
> > > > - Fix out case to set R10 and R11 correctly when user space handled port
> > > >     out.
> > > > ---
> > > >    arch/x86/kvm/vmx/tdx.c | 67 ++++++++++++++++++++++++++++++++++++++++++
> > > >    1 file changed, 67 insertions(+)
> > > > 
> > > > diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> > > > index a2caf2ae838c..55fc6cc6c816 100644
> > > > --- a/arch/x86/kvm/vmx/tdx.c
> > > > +++ b/arch/x86/kvm/vmx/tdx.c
> > > > @@ -1152,6 +1152,71 @@ static int tdx_emulate_hlt(struct kvm_vcpu *vcpu)
> > > >    	return kvm_emulate_halt_noskip(vcpu);
> > > >    }
> > > > +static int tdx_complete_pio_out(struct kvm_vcpu *vcpu)
> > > > +{
> > > > +	tdvmcall_set_return_code(vcpu, TDVMCALL_SUCCESS);
> > > > +	tdvmcall_set_return_val(vcpu, 0);
> > > > +	return 1;
> > > > +}
> > > > +
> > > > +static int tdx_complete_pio_in(struct kvm_vcpu *vcpu)
> > > > +{
> > > > +	struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
> > > > +	unsigned long val = 0;
> > > > +	int ret;
> > > > +
> > > > +	WARN_ON_ONCE(vcpu->arch.pio.count != 1);
> > > > +
> > > > +	ret = ctxt->ops->pio_in_emulated(ctxt, vcpu->arch.pio.size,
> > > > +					 vcpu->arch.pio.port, &val, 1);
> > > > +	WARN_ON_ONCE(!ret);
> > > > +
> > > > +	tdvmcall_set_return_code(vcpu, TDVMCALL_SUCCESS);
> > > > +	tdvmcall_set_return_val(vcpu, val);
> > > > +
> > > > +	return 1;
> > > > +}
> > > > +
> > > > +static int tdx_emulate_io(struct kvm_vcpu *vcpu)
> > > > +{
> > > > +	struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
> > > > +	unsigned long val = 0;
> > > > +	unsigned int port;
> > > > +	int size, ret;
> > > > +	bool write;
> > > > +
> > > > +	++vcpu->stat.io_exits;
> > > > +
> > > > +	size = tdvmcall_a0_read(vcpu);
> > > > +	write = tdvmcall_a1_read(vcpu);
> > > > +	port = tdvmcall_a2_read(vcpu);
> > > > +
> > > > +	if (size != 1 && size != 2 && size != 4) {
> > > > +		tdvmcall_set_return_code(vcpu, TDVMCALL_INVALID_OPERAND);
> > > > +		return 1;
> > > > +	}
> > > > +
> > > > +	if (write) {
> > > > +		val = tdvmcall_a3_read(vcpu);
> > > > +		ret = ctxt->ops->pio_out_emulated(ctxt, size, port, &val, 1);
> > > > +
> > > > +		/* No need for a complete_userspace_io callback. */
> > > I am confused about the comment.
> > > 
> > > The code below sets the complete_userspace_io callback for write case,
> > > i.e. tdx_complete_pio_out().
> > You're correct. This comment is stale and should be removed it.
> Also, since the tdx_complete_pio_out() is installed as complete_userspace_io
> callback for write, it's more reasonable to move the reset of pio.count into
> tdx_complete_pio_out().
> How about the following fixup:

It makes sense. It matches better with other complete callbacks
for tdx_complete_pio_out() to clear pio.count to 0.


> diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> index 9ead46cb75ab..b43bb8ccddb9 100644
> --- a/arch/x86/kvm/vmx/tdx.c
> +++ b/arch/x86/kvm/vmx/tdx.c
> @@ -1115,6 +1115,7 @@ static int tdx_emulate_hlt(struct kvm_vcpu *vcpu)
> 
>  static int tdx_complete_pio_out(struct kvm_vcpu *vcpu)
>  {
> +       vcpu->arch.pio.count = 0;
>         tdvmcall_set_return_code(vcpu, TDVMCALL_SUCCESS);
>         tdvmcall_set_return_val(vcpu, 0);
>         return 1;
> @@ -1159,15 +1160,13 @@ static int tdx_emulate_io(struct kvm_vcpu *vcpu)
>         if (write) {
>                 val = tdvmcall_a3_read(vcpu);
>                 ret = ctxt->ops->pio_out_emulated(ctxt, size, port, &val,
> 1);
> -
> -               /* No need for a complete_userspace_io callback. */
> -               vcpu->arch.pio.count = 0;
> -       } else
> +       } else {
>                 ret = ctxt->ops->pio_in_emulated(ctxt, size, port, &val, 1);
> +       }
> 
> -       if (ret)
> +       if (ret) {
>                 tdvmcall_set_return_val(vcpu, val);
> -       else {
> +       } else {
>                 if (write)
>                         vcpu->arch.complete_userspace_io =
> tdx_complete_pio_out;
>                 else
> 
>
diff mbox series

Patch

diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index a2caf2ae838c..55fc6cc6c816 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -1152,6 +1152,71 @@  static int tdx_emulate_hlt(struct kvm_vcpu *vcpu)
 	return kvm_emulate_halt_noskip(vcpu);
 }
 
+static int tdx_complete_pio_out(struct kvm_vcpu *vcpu)
+{
+	tdvmcall_set_return_code(vcpu, TDVMCALL_SUCCESS);
+	tdvmcall_set_return_val(vcpu, 0);
+	return 1;
+}
+
+static int tdx_complete_pio_in(struct kvm_vcpu *vcpu)
+{
+	struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
+	unsigned long val = 0;
+	int ret;
+
+	WARN_ON_ONCE(vcpu->arch.pio.count != 1);
+
+	ret = ctxt->ops->pio_in_emulated(ctxt, vcpu->arch.pio.size,
+					 vcpu->arch.pio.port, &val, 1);
+	WARN_ON_ONCE(!ret);
+
+	tdvmcall_set_return_code(vcpu, TDVMCALL_SUCCESS);
+	tdvmcall_set_return_val(vcpu, val);
+
+	return 1;
+}
+
+static int tdx_emulate_io(struct kvm_vcpu *vcpu)
+{
+	struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;
+	unsigned long val = 0;
+	unsigned int port;
+	int size, ret;
+	bool write;
+
+	++vcpu->stat.io_exits;
+
+	size = tdvmcall_a0_read(vcpu);
+	write = tdvmcall_a1_read(vcpu);
+	port = tdvmcall_a2_read(vcpu);
+
+	if (size != 1 && size != 2 && size != 4) {
+		tdvmcall_set_return_code(vcpu, TDVMCALL_INVALID_OPERAND);
+		return 1;
+	}
+
+	if (write) {
+		val = tdvmcall_a3_read(vcpu);
+		ret = ctxt->ops->pio_out_emulated(ctxt, size, port, &val, 1);
+
+		/* No need for a complete_userspace_io callback. */
+		vcpu->arch.pio.count = 0;
+	} else
+		ret = ctxt->ops->pio_in_emulated(ctxt, size, port, &val, 1);
+
+	if (ret)
+		tdvmcall_set_return_val(vcpu, val);
+	else {
+		if (write)
+			vcpu->arch.complete_userspace_io = tdx_complete_pio_out;
+		else
+			vcpu->arch.complete_userspace_io = tdx_complete_pio_in;
+	}
+
+	return ret;
+}
+
 static int handle_tdvmcall(struct kvm_vcpu *vcpu)
 {
 	if (tdvmcall_exit_type(vcpu))
@@ -1162,6 +1227,8 @@  static int handle_tdvmcall(struct kvm_vcpu *vcpu)
 		return tdx_emulate_cpuid(vcpu);
 	case EXIT_REASON_HLT:
 		return tdx_emulate_hlt(vcpu);
+	case EXIT_REASON_IO_INSTRUCTION:
+		return tdx_emulate_io(vcpu);
 	default:
 		break;
 	}