diff mbox series

[v2,07/58] i386/tdx: Introduce is_tdx_vm() helper and cache tdx_guest object

Message ID 20230818095041.1973309-8-xiaoyao.li@intel.com (mailing list archive)
State New, archived
Headers show
Series TDX QEMU support | expand

Commit Message

Xiaoyao Li Aug. 18, 2023, 9:49 a.m. UTC 
It will need special handling for TDX VMs all around the QEMU.
Introduce is_tdx_vm() helper to query if it's a TDX VM.

Cache tdx_guest object thus no need to cast from ms->cgs every time.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
---
 target/i386/kvm/tdx.c | 13 +++++++++++++
 target/i386/kvm/tdx.h | 10 ++++++++++
 2 files changed, 23 insertions(+)

Comments

Daniel P. Berrangé Aug. 21, 2023, 8:48 a.m. UTC | #1 
On Fri, Aug 18, 2023 at 05:49:50AM -0400, Xiaoyao Li wrote:
> It will need special handling for TDX VMs all around the QEMU.
> Introduce is_tdx_vm() helper to query if it's a TDX VM.
> 
> Cache tdx_guest object thus no need to cast from ms->cgs every time.
> 
> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
> Acked-by: Gerd Hoffmann <kraxel@redhat.com>
> ---
>  target/i386/kvm/tdx.c | 13 +++++++++++++
>  target/i386/kvm/tdx.h | 10 ++++++++++
>  2 files changed, 23 insertions(+)
> 
> diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c
> index 255c47a2a553..56cb826f6125 100644
> --- a/target/i386/kvm/tdx.c
> +++ b/target/i386/kvm/tdx.c
> @@ -21,8 +21,16 @@
>  #include "kvm_i386.h"
>  #include "tdx.h"
>  
> +static TdxGuest *tdx_guest;
> +
>  static struct kvm_tdx_capabilities *tdx_caps;
>  
> +/* It's valid after kvm_confidential_guest_init()->kvm_tdx_init() */
> +bool is_tdx_vm(void)
> +{
> +    return !!tdx_guest;
> +}
> +
>  enum tdx_ioctl_level{
>      TDX_PLATFORM_IOCTL,
>      TDX_VM_IOCTL,
> @@ -109,10 +117,15 @@ static void get_tdx_capabilities(void)
>  
>  int tdx_kvm_init(MachineState *ms, Error **errp)
>  {
> +    TdxGuest *tdx = (TdxGuest *)object_dynamic_cast(OBJECT(ms->cgs),
> +                                                    TYPE_TDX_GUEST);

This method can return NULL.  Presumably tdx_kvm_init() should only
be called if we already checked  ms->cgs == TYPE_TDX_GUEST. If so
then use object_dynamic_cast_assert() instead.

> +
>      if (!tdx_caps) {
>          get_tdx_capabilities();
>      }
>  
> +    tdx_guest = tdx;
> +
>      return 0;
>  }
>  
> diff --git a/target/i386/kvm/tdx.h b/target/i386/kvm/tdx.h
> index c8a23d95258d..4036ca2f3f99 100644
> --- a/target/i386/kvm/tdx.h
> +++ b/target/i386/kvm/tdx.h
> @@ -1,6 +1,10 @@
>  #ifndef QEMU_I386_TDX_H
>  #define QEMU_I386_TDX_H
>  
> +#ifndef CONFIG_USER_ONLY
> +#include CONFIG_DEVICES /* CONFIG_TDX */
> +#endif
> +
>  #include "exec/confidential-guest-support.h"
>  
>  #define TYPE_TDX_GUEST "tdx-guest"
> @@ -16,6 +20,12 @@ typedef struct TdxGuest {
>      uint64_t attributes;    /* TD attributes */
>  } TdxGuest;
>  
> +#ifdef CONFIG_TDX
> +bool is_tdx_vm(void);
> +#else
> +#define is_tdx_vm() 0
> +#endif /* CONFIG_TDX */
> +
>  int tdx_kvm_init(MachineState *ms, Error **errp);
>  
>  #endif /* QEMU_I386_TDX_H */
> -- 
> 2.34.1
> 

With regards,
Daniel
Xiaoyao Li Aug. 22, 2023, 7:46 a.m. UTC | #2 
On 8/21/2023 4:48 PM, Daniel P. Berrangé wrote:
> On Fri, Aug 18, 2023 at 05:49:50AM -0400, Xiaoyao Li wrote:
>> It will need special handling for TDX VMs all around the QEMU.
>> Introduce is_tdx_vm() helper to query if it's a TDX VM.
>>
>> Cache tdx_guest object thus no need to cast from ms->cgs every time.
>>
>> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
>> Acked-by: Gerd Hoffmann <kraxel@redhat.com>
>> ---
>>   target/i386/kvm/tdx.c | 13 +++++++++++++
>>   target/i386/kvm/tdx.h | 10 ++++++++++
>>   2 files changed, 23 insertions(+)
>>
>> diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c
>> index 255c47a2a553..56cb826f6125 100644
>> --- a/target/i386/kvm/tdx.c
>> +++ b/target/i386/kvm/tdx.c
>> @@ -21,8 +21,16 @@
>>   #include "kvm_i386.h"
>>   #include "tdx.h"
>>   
>> +static TdxGuest *tdx_guest;
>> +
>>   static struct kvm_tdx_capabilities *tdx_caps;
>>   
>> +/* It's valid after kvm_confidential_guest_init()->kvm_tdx_init() */
>> +bool is_tdx_vm(void)
>> +{
>> +    return !!tdx_guest;
>> +}
>> +
>>   enum tdx_ioctl_level{
>>       TDX_PLATFORM_IOCTL,
>>       TDX_VM_IOCTL,
>> @@ -109,10 +117,15 @@ static void get_tdx_capabilities(void)
>>   
>>   int tdx_kvm_init(MachineState *ms, Error **errp)
>>   {
>> +    TdxGuest *tdx = (TdxGuest *)object_dynamic_cast(OBJECT(ms->cgs),
>> +                                                    TYPE_TDX_GUEST);
> 
> This method can return NULL.  Presumably tdx_kvm_init() should only
> be called if we already checked  ms->cgs == TYPE_TDX_GUEST. If so
> then use object_dynamic_cast_assert() instead.
> 

object_dynamic_cast_assert() is for OBJECT_CHECK() and INTERFACE_CHECK().

So I will use TDX_GUEST(OBJECT(ms->cgs)) (introduced in patch 2) 
instead, which is the wrapper of OBJECT_CHECK().
diff mbox series

Patch

diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c
index 255c47a2a553..56cb826f6125 100644
--- a/target/i386/kvm/tdx.c
+++ b/target/i386/kvm/tdx.c
@@ -21,8 +21,16 @@ 
 #include "kvm_i386.h"
 #include "tdx.h"
 
+static TdxGuest *tdx_guest;
+
 static struct kvm_tdx_capabilities *tdx_caps;
 
+/* It's valid after kvm_confidential_guest_init()->kvm_tdx_init() */
+bool is_tdx_vm(void)
+{
+    return !!tdx_guest;
+}
+
 enum tdx_ioctl_level{
     TDX_PLATFORM_IOCTL,
     TDX_VM_IOCTL,
@@ -109,10 +117,15 @@  static void get_tdx_capabilities(void)
 
 int tdx_kvm_init(MachineState *ms, Error **errp)
 {
+    TdxGuest *tdx = (TdxGuest *)object_dynamic_cast(OBJECT(ms->cgs),
+                                                    TYPE_TDX_GUEST);
+
     if (!tdx_caps) {
         get_tdx_capabilities();
     }
 
+    tdx_guest = tdx;
+
     return 0;
 }
 
diff --git a/target/i386/kvm/tdx.h b/target/i386/kvm/tdx.h
index c8a23d95258d..4036ca2f3f99 100644
--- a/target/i386/kvm/tdx.h
+++ b/target/i386/kvm/tdx.h
@@ -1,6 +1,10 @@ 
 #ifndef QEMU_I386_TDX_H
 #define QEMU_I386_TDX_H
 
+#ifndef CONFIG_USER_ONLY
+#include CONFIG_DEVICES /* CONFIG_TDX */
+#endif
+
 #include "exec/confidential-guest-support.h"
 
 #define TYPE_TDX_GUEST "tdx-guest"
@@ -16,6 +20,12 @@  typedef struct TdxGuest {
     uint64_t attributes;    /* TD attributes */
 } TdxGuest;
 
+#ifdef CONFIG_TDX
+bool is_tdx_vm(void);
+#else
+#define is_tdx_vm() 0
+#endif /* CONFIG_TDX */
+
 int tdx_kvm_init(MachineState *ms, Error **errp);
 
 #endif /* QEMU_I386_TDX_H */