diff mbox series

[v8,022/103] KVM: TDX: Add place holder for TDX VM specific mem_enc_op ioctl

Message ID 2d65bd56a7ab8c0776f5c6b7c8481dd45ad96794.1659854790.git.isaku.yamahata@intel.com (mailing list archive)
State New, archived
Headers show
Series KVM TDX basic feature support | expand

Commit Message

Isaku Yamahata Aug. 7, 2022, 10:01 p.m. UTC 
From: Isaku Yamahata <isaku.yamahata@intel.com>

Add a place holder function for TDX specific VM-scoped ioctl as mem_enc_op.
TDX specific sub-commands will be added to retrieve/pass TDX specific
parameters.

KVM_MEMORY_ENCRYPT_OP was introduced for VM-scoped operations specific for
guest state-protected VM.  It defined subcommands for technology-specific
operations under KVM_MEMORY_ENCRYPT_OP.  Despite its name, the subcommands
are not limited to memory encryption, but various technology-specific
operations are defined.  It's natural to repurpose KVM_MEMORY_ENCRYPT_OP
for TDX specific operations and define subcommands.

TDX requires VM-scoped TDX-specific operations for device model, for
example, qemu.  Getting system-wide parameters, TDX-specific VM
initialization.

Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
---
 arch/x86/kvm/vmx/main.c    |  9 +++++++++
 arch/x86/kvm/vmx/tdx.c     | 26 ++++++++++++++++++++++++++
 arch/x86/kvm/vmx/x86_ops.h |  4 ++++
 3 files changed, 39 insertions(+)

Comments

Binbin Wu Aug. 29, 2022, 4:07 a.m. UTC | #1 
On 2022/8/8 6:01, isaku.yamahata@intel.com wrote:
> From: Isaku Yamahata <isaku.yamahata@intel.com>
>
> Add a place holder function for TDX specific VM-scoped ioctl as mem_enc_op.
> TDX specific sub-commands will be added to retrieve/pass TDX specific
> parameters.
>
> KVM_MEMORY_ENCRYPT_OP was introduced for VM-scoped operations specific for
> guest state-protected VM.  It defined subcommands for technology-specific
> operations under KVM_MEMORY_ENCRYPT_OP.  Despite its name, the subcommands
> are not limited to memory encryption, but various technology-specific
> operations are defined.  It's natural to repurpose KVM_MEMORY_ENCRYPT_OP
> for TDX specific operations and define subcommands.
>
> TDX requires VM-scoped TDX-specific operations for device model, for
> example, qemu.  Getting system-wide parameters, TDX-specific VM
> initialization.
>
> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
> ---
>   arch/x86/kvm/vmx/main.c    |  9 +++++++++
>   arch/x86/kvm/vmx/tdx.c     | 26 ++++++++++++++++++++++++++
>   arch/x86/kvm/vmx/x86_ops.h |  4 ++++
>   3 files changed, 39 insertions(+)
>
> diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
> index 7b497ed1f21c..067f5de56c53 100644
> --- a/arch/x86/kvm/vmx/main.c
> +++ b/arch/x86/kvm/vmx/main.c
> @@ -73,6 +73,14 @@ static void vt_vm_free(struct kvm *kvm)
>   		return tdx_vm_free(kvm);
>   }
>   
> +static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
> +{
> +	if (!is_td(kvm))
> +		return -ENOTTY;
> +
> +	return tdx_vm_ioctl(kvm, argp);
> +}
> +
>   struct kvm_x86_ops vt_x86_ops __initdata = {
>   	.name = "kvm_intel",
>   
> @@ -214,6 +222,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
>   	.vcpu_deliver_sipi_vector = kvm_vcpu_deliver_sipi_vector,
>   
>   	.dev_mem_enc_ioctl = tdx_dev_ioctl,
> +	.mem_enc_ioctl = vt_mem_enc_ioctl,

suggeust to align the interafce/function name style with the scop.

patch 21 and 27 have the scope in interafce names(dev / vcpu), may be 
clearer to use  vcpu_mem_enc_ioctl?



>   };
>   
>   struct kvm_x86_init_ops vt_init_ops __initdata = {
> diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> index 16c6570dbe52..d3b9f653da4b 100644
> --- a/arch/x86/kvm/vmx/tdx.c
> +++ b/arch/x86/kvm/vmx/tdx.c
> @@ -424,6 +424,32 @@ int tdx_dev_ioctl(void __user *argp)
>   	return 0;
>   }
>   
> +int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
> +{
> +	struct kvm_tdx_cmd tdx_cmd;
> +	int r;
> +
> +	if (copy_from_user(&tdx_cmd, argp, sizeof(struct kvm_tdx_cmd)))
> +		return -EFAULT;
> +	if (tdx_cmd.error || tdx_cmd.unused)
> +		return -EINVAL;
> +
> +	mutex_lock(&kvm->lock);
> +
> +	switch (tdx_cmd.id) {
> +	default:
> +		r = -EINVAL;
> +		goto out;
> +	}
> +
> +	if (copy_to_user(argp, &tdx_cmd, sizeof(struct kvm_tdx_cmd)))
> +		r = -EFAULT;
> +
> +out:
> +	mutex_unlock(&kvm->lock);
> +	return r;
> +}
> +
>   int __init tdx_module_setup(void)
>   {
>   	const struct tdsysinfo_struct *tdsysinfo;
> diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
> index 02490515d190..f0fe40c7ac34 100644
> --- a/arch/x86/kvm/vmx/x86_ops.h
> +++ b/arch/x86/kvm/vmx/x86_ops.h
> @@ -137,6 +137,8 @@ int tdx_dev_ioctl(void __user *argp);
>   int tdx_vm_init(struct kvm *kvm);
>   void tdx_mmu_release_hkid(struct kvm *kvm);
>   void tdx_vm_free(struct kvm *kvm);
> +
> +int tdx_vm_ioctl(struct kvm *kvm, void __user *argp);
>   #else
>   static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return 0; }
>   static inline bool tdx_is_vm_type_supported(unsigned long type) { return false; }
> @@ -147,6 +149,8 @@ static inline int tdx_vm_init(struct kvm *kvm) { return -EOPNOTSUPP; }
>   static inline void tdx_mmu_release_hkid(struct kvm *kvm) {}
>   static inline void tdx_flush_shadow_all_private(struct kvm *kvm) {}
>   static inline void tdx_vm_free(struct kvm *kvm) {}
> +
> +static inline int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) { return -EOPNOTSUPP; }
>   #endif
>   
>   #endif /* __KVM_X86_VMX_X86_OPS_H */
Isaku Yamahata Aug. 29, 2022, 7:17 p.m. UTC | #2 
On Mon, Aug 29, 2022 at 12:07:55PM +0800,
Binbin Wu <binbin.wu@linux.intel.com> wrote:

> > diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
> > index 7b497ed1f21c..067f5de56c53 100644
> > --- a/arch/x86/kvm/vmx/main.c
> > +++ b/arch/x86/kvm/vmx/main.c
> > @@ -73,6 +73,14 @@ static void vt_vm_free(struct kvm *kvm)
> >   		return tdx_vm_free(kvm);
> >   }
> > +static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
> > +{
> > +	if (!is_td(kvm))
> > +		return -ENOTTY;
> > +
> > +	return tdx_vm_ioctl(kvm, argp);
> > +}
> > +
> >   struct kvm_x86_ops vt_x86_ops __initdata = {
> >   	.name = "kvm_intel",
> > @@ -214,6 +222,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
> >   	.vcpu_deliver_sipi_vector = kvm_vcpu_deliver_sipi_vector,
> >   	.dev_mem_enc_ioctl = tdx_dev_ioctl,
> > +	.mem_enc_ioctl = vt_mem_enc_ioctl,
> 
> suggeust to align the interafce/function name style with the scop.
> 
> patch 21 and 27 have the scope in interafce names(dev / vcpu), may be
> clearer to use  vcpu_mem_enc_ioctl?

This is a matter of preference.  I intentionally chose to drop mem_enc part
because actually KVM_MEMORY_ENCRYPT_OP is abused for TDX or SEV(-SNP) specific
operation.  Subcommand for KVM_MEMORY_ENCRYPT_OP is not directly related to
memory encryption.  It should be KVM_CONFIDENTIAL_OP or something.
Unfortunately it's too late to rename it.
Yuan Yao Aug. 31, 2022, 2:18 a.m. UTC | #3 
On Sun, Aug 07, 2022 at 03:01:07PM -0700, isaku.yamahata@intel.com wrote:
> From: Isaku Yamahata <isaku.yamahata@intel.com>
>
> Add a place holder function for TDX specific VM-scoped ioctl as mem_enc_op.
> TDX specific sub-commands will be added to retrieve/pass TDX specific
> parameters.
>
> KVM_MEMORY_ENCRYPT_OP was introduced for VM-scoped operations specific for
> guest state-protected VM.  It defined subcommands for technology-specific
> operations under KVM_MEMORY_ENCRYPT_OP.  Despite its name, the subcommands
> are not limited to memory encryption, but various technology-specific
> operations are defined.  It's natural to repurpose KVM_MEMORY_ENCRYPT_OP
> for TDX specific operations and define subcommands.
>
> TDX requires VM-scoped TDX-specific operations for device model, for
> example, qemu.  Getting system-wide parameters, TDX-specific VM
> initialization.
>
> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
> ---
>  arch/x86/kvm/vmx/main.c    |  9 +++++++++
>  arch/x86/kvm/vmx/tdx.c     | 26 ++++++++++++++++++++++++++
>  arch/x86/kvm/vmx/x86_ops.h |  4 ++++
>  3 files changed, 39 insertions(+)
>
> diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
> index 7b497ed1f21c..067f5de56c53 100644
> --- a/arch/x86/kvm/vmx/main.c
> +++ b/arch/x86/kvm/vmx/main.c
> @@ -73,6 +73,14 @@ static void vt_vm_free(struct kvm *kvm)
>  		return tdx_vm_free(kvm);
>  }
>
> +static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
> +{
> +	if (!is_td(kvm))
> +		return -ENOTTY;
> +
> +	return tdx_vm_ioctl(kvm, argp);
> +}
> +
>  struct kvm_x86_ops vt_x86_ops __initdata = {
>  	.name = "kvm_intel",
>
> @@ -214,6 +222,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
>  	.vcpu_deliver_sipi_vector = kvm_vcpu_deliver_sipi_vector,
>
>  	.dev_mem_enc_ioctl = tdx_dev_ioctl,
> +	.mem_enc_ioctl = vt_mem_enc_ioctl,
>  };
>
>  struct kvm_x86_init_ops vt_init_ops __initdata = {
> diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
> index 16c6570dbe52..d3b9f653da4b 100644
> --- a/arch/x86/kvm/vmx/tdx.c
> +++ b/arch/x86/kvm/vmx/tdx.c
> @@ -424,6 +424,32 @@ int tdx_dev_ioctl(void __user *argp)
>  	return 0;
>  }
>
> +int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
> +{
> +	struct kvm_tdx_cmd tdx_cmd;
> +	int r;
> +
> +	if (copy_from_user(&tdx_cmd, argp, sizeof(struct kvm_tdx_cmd)))

Minor: sizeof(tdx_cmd), escape from type change & better readability.

> +		return -EFAULT;
> +	if (tdx_cmd.error || tdx_cmd.unused)
> +		return -EINVAL;
> +
> +	mutex_lock(&kvm->lock);
> +
> +	switch (tdx_cmd.id) {
> +	default:
> +		r = -EINVAL;
> +		goto out;
> +	}
> +
> +	if (copy_to_user(argp, &tdx_cmd, sizeof(struct kvm_tdx_cmd)))

Ditto

> +		r = -EFAULT;
> +
> +out:
> +	mutex_unlock(&kvm->lock);
> +	return r;
> +}
> +
>  int __init tdx_module_setup(void)
>  {
>  	const struct tdsysinfo_struct *tdsysinfo;
> diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
> index 02490515d190..f0fe40c7ac34 100644
> --- a/arch/x86/kvm/vmx/x86_ops.h
> +++ b/arch/x86/kvm/vmx/x86_ops.h
> @@ -137,6 +137,8 @@ int tdx_dev_ioctl(void __user *argp);
>  int tdx_vm_init(struct kvm *kvm);
>  void tdx_mmu_release_hkid(struct kvm *kvm);
>  void tdx_vm_free(struct kvm *kvm);
> +
> +int tdx_vm_ioctl(struct kvm *kvm, void __user *argp);
>  #else
>  static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return 0; }
>  static inline bool tdx_is_vm_type_supported(unsigned long type) { return false; }
> @@ -147,6 +149,8 @@ static inline int tdx_vm_init(struct kvm *kvm) { return -EOPNOTSUPP; }
>  static inline void tdx_mmu_release_hkid(struct kvm *kvm) {}
>  static inline void tdx_flush_shadow_all_private(struct kvm *kvm) {}
>  static inline void tdx_vm_free(struct kvm *kvm) {}
> +
> +static inline int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) { return -EOPNOTSUPP; }
>  #endif
>
>  #endif /* __KVM_X86_VMX_X86_OPS_H */
> --
> 2.25.1
>
diff mbox series

Patch

diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 7b497ed1f21c..067f5de56c53 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -73,6 +73,14 @@  static void vt_vm_free(struct kvm *kvm)
 		return tdx_vm_free(kvm);
 }
 
+static int vt_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
+{
+	if (!is_td(kvm))
+		return -ENOTTY;
+
+	return tdx_vm_ioctl(kvm, argp);
+}
+
 struct kvm_x86_ops vt_x86_ops __initdata = {
 	.name = "kvm_intel",
 
@@ -214,6 +222,7 @@  struct kvm_x86_ops vt_x86_ops __initdata = {
 	.vcpu_deliver_sipi_vector = kvm_vcpu_deliver_sipi_vector,
 
 	.dev_mem_enc_ioctl = tdx_dev_ioctl,
+	.mem_enc_ioctl = vt_mem_enc_ioctl,
 };
 
 struct kvm_x86_init_ops vt_init_ops __initdata = {
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 16c6570dbe52..d3b9f653da4b 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -424,6 +424,32 @@  int tdx_dev_ioctl(void __user *argp)
 	return 0;
 }
 
+int tdx_vm_ioctl(struct kvm *kvm, void __user *argp)
+{
+	struct kvm_tdx_cmd tdx_cmd;
+	int r;
+
+	if (copy_from_user(&tdx_cmd, argp, sizeof(struct kvm_tdx_cmd)))
+		return -EFAULT;
+	if (tdx_cmd.error || tdx_cmd.unused)
+		return -EINVAL;
+
+	mutex_lock(&kvm->lock);
+
+	switch (tdx_cmd.id) {
+	default:
+		r = -EINVAL;
+		goto out;
+	}
+
+	if (copy_to_user(argp, &tdx_cmd, sizeof(struct kvm_tdx_cmd)))
+		r = -EFAULT;
+
+out:
+	mutex_unlock(&kvm->lock);
+	return r;
+}
+
 int __init tdx_module_setup(void)
 {
 	const struct tdsysinfo_struct *tdsysinfo;
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index 02490515d190..f0fe40c7ac34 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -137,6 +137,8 @@  int tdx_dev_ioctl(void __user *argp);
 int tdx_vm_init(struct kvm *kvm);
 void tdx_mmu_release_hkid(struct kvm *kvm);
 void tdx_vm_free(struct kvm *kvm);
+
+int tdx_vm_ioctl(struct kvm *kvm, void __user *argp);
 #else
 static inline int tdx_hardware_setup(struct kvm_x86_ops *x86_ops) { return 0; }
 static inline bool tdx_is_vm_type_supported(unsigned long type) { return false; }
@@ -147,6 +149,8 @@  static inline int tdx_vm_init(struct kvm *kvm) { return -EOPNOTSUPP; }
 static inline void tdx_mmu_release_hkid(struct kvm *kvm) {}
 static inline void tdx_flush_shadow_all_private(struct kvm *kvm) {}
 static inline void tdx_vm_free(struct kvm *kvm) {}
+
+static inline int tdx_vm_ioctl(struct kvm *kvm, void __user *argp) { return -EOPNOTSUPP; }
 #endif
 
 #endif /* __KVM_X86_VMX_X86_OPS_H */