diff mbox series

[v4,2/6] LoongArch: KVM: Add hypercall instruction emulation support

Message ID 20240201031950.3225626-3-maobibo@loongson.cn
State New
Headers
Series LoongArch: Add pv ipi support on LoongArch VM |

Commit Message

maobibo Feb. 1, 2024, 3:19 a.m. UTC 
  On LoongArch system, hypercall instruction is supported when system
runs on VM mode. This patch adds dummy function with hypercall
instruction emulation, rather than inject EXCCODE_INE invalid
instruction exception.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
---
 arch/loongarch/include/asm/Kbuild      |  1 -
 arch/loongarch/include/asm/kvm_para.h  | 26 ++++++++++++++++++++++++++
 arch/loongarch/include/uapi/asm/Kbuild |  2 --
 arch/loongarch/kvm/exit.c              | 10 ++++++++++
 4 files changed, 36 insertions(+), 3 deletions(-)
 create mode 100644 arch/loongarch/include/asm/kvm_para.h
 delete mode 100644 arch/loongarch/include/uapi/asm/Kbuild

Comments

Huacai Chen Feb. 19, 2024, 2:41 a.m. UTC | #1 
Hi, Bibo,

On Thu, Feb 1, 2024 at 11:19 AM Bibo Mao <maobibo@loongson.cn> wrote:
>
> On LoongArch system, hypercall instruction is supported when system
> runs on VM mode. This patch adds dummy function with hypercall
> instruction emulation, rather than inject EXCCODE_INE invalid
> instruction exception.
>
> Signed-off-by: Bibo Mao <maobibo@loongson.cn>
> ---
>  arch/loongarch/include/asm/Kbuild      |  1 -
>  arch/loongarch/include/asm/kvm_para.h  | 26 ++++++++++++++++++++++++++
>  arch/loongarch/include/uapi/asm/Kbuild |  2 --
>  arch/loongarch/kvm/exit.c              | 10 ++++++++++
>  4 files changed, 36 insertions(+), 3 deletions(-)
>  create mode 100644 arch/loongarch/include/asm/kvm_para.h
>  delete mode 100644 arch/loongarch/include/uapi/asm/Kbuild
>
> diff --git a/arch/loongarch/include/asm/Kbuild b/arch/loongarch/include/asm/Kbuild
> index 93783fa24f6e..22991a6f0e2b 100644
> --- a/arch/loongarch/include/asm/Kbuild
> +++ b/arch/loongarch/include/asm/Kbuild
> @@ -23,4 +23,3 @@ generic-y += poll.h
>  generic-y += param.h
>  generic-y += posix_types.h
>  generic-y += resource.h
> -generic-y += kvm_para.h
> diff --git a/arch/loongarch/include/asm/kvm_para.h b/arch/loongarch/include/asm/kvm_para.h
> new file mode 100644
> index 000000000000..9425d3b7e486
> --- /dev/null
> +++ b/arch/loongarch/include/asm/kvm_para.h
> @@ -0,0 +1,26 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +#ifndef _ASM_LOONGARCH_KVM_PARA_H
> +#define _ASM_LOONGARCH_KVM_PARA_H
> +
> +/*
> + * LoongArch hypcall return code
Maybe using "hypercall" in comments is better.

> + */
> +#define KVM_HC_STATUS_SUCCESS          0
> +#define KVM_HC_INVALID_CODE            -1UL
> +#define KVM_HC_INVALID_PARAMETER       -2UL
Maybe KVM_HCALL_SUCCESS/KVM_HCALL_INVALID_CODE/KVM_HCALL_PARAMETER is better.

Huacai

> +
> +static inline unsigned int kvm_arch_para_features(void)
> +{
> +       return 0;
> +}
> +
> +static inline unsigned int kvm_arch_para_hints(void)
> +{
> +       return 0;
> +}
> +
> +static inline bool kvm_check_and_clear_guest_paused(void)
> +{
> +       return false;
> +}
> +#endif /* _ASM_LOONGARCH_KVM_PARA_H */
> diff --git a/arch/loongarch/include/uapi/asm/Kbuild b/arch/loongarch/include/uapi/asm/Kbuild
> deleted file mode 100644
> index 4aa680ca2e5f..000000000000
> --- a/arch/loongarch/include/uapi/asm/Kbuild
> +++ /dev/null
> @@ -1,2 +0,0 @@
> -# SPDX-License-Identifier: GPL-2.0
> -generic-y += kvm_para.h
> diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c
> index ed1d89d53e2e..d15c71320a11 100644
> --- a/arch/loongarch/kvm/exit.c
> +++ b/arch/loongarch/kvm/exit.c
> @@ -685,6 +685,15 @@ static int kvm_handle_lasx_disabled(struct kvm_vcpu *vcpu)
>         return RESUME_GUEST;
>  }
>
> +static int kvm_handle_hypcall(struct kvm_vcpu *vcpu)
> +{
> +       update_pc(&vcpu->arch);
> +
> +       /* Treat it as noop intruction, only set return value */
> +       vcpu->arch.gprs[LOONGARCH_GPR_A0] = KVM_HC_INVALID_CODE;
> +       return RESUME_GUEST;
> +}
> +
>  /*
>   * LoongArch KVM callback handling for unimplemented guest exiting
>   */
> @@ -716,6 +725,7 @@ static exit_handle_fn kvm_fault_tables[EXCCODE_INT_START] = {
>         [EXCCODE_LSXDIS]                = kvm_handle_lsx_disabled,
>         [EXCCODE_LASXDIS]               = kvm_handle_lasx_disabled,
>         [EXCCODE_GSPR]                  = kvm_handle_gspr,
> +       [EXCCODE_HVC]                   = kvm_handle_hypcall,
>  };
>
>  int kvm_handle_fault(struct kvm_vcpu *vcpu, int fault)
> --
> 2.39.3
>
maobibo Feb. 19, 2024, 4:01 a.m. UTC | #2 
On 2024/2/19 上午10:41, Huacai Chen wrote:
> Hi, Bibo,
> 
> On Thu, Feb 1, 2024 at 11:19 AM Bibo Mao <maobibo@loongson.cn> wrote:
>>
>> On LoongArch system, hypercall instruction is supported when system
>> runs on VM mode. This patch adds dummy function with hypercall
>> instruction emulation, rather than inject EXCCODE_INE invalid
>> instruction exception.
>>
>> Signed-off-by: Bibo Mao <maobibo@loongson.cn>
>> ---
>>   arch/loongarch/include/asm/Kbuild      |  1 -
>>   arch/loongarch/include/asm/kvm_para.h  | 26 ++++++++++++++++++++++++++
>>   arch/loongarch/include/uapi/asm/Kbuild |  2 --
>>   arch/loongarch/kvm/exit.c              | 10 ++++++++++
>>   4 files changed, 36 insertions(+), 3 deletions(-)
>>   create mode 100644 arch/loongarch/include/asm/kvm_para.h
>>   delete mode 100644 arch/loongarch/include/uapi/asm/Kbuild
>>
>> diff --git a/arch/loongarch/include/asm/Kbuild b/arch/loongarch/include/asm/Kbuild
>> index 93783fa24f6e..22991a6f0e2b 100644
>> --- a/arch/loongarch/include/asm/Kbuild
>> +++ b/arch/loongarch/include/asm/Kbuild
>> @@ -23,4 +23,3 @@ generic-y += poll.h
>>   generic-y += param.h
>>   generic-y += posix_types.h
>>   generic-y += resource.h
>> -generic-y += kvm_para.h
>> diff --git a/arch/loongarch/include/asm/kvm_para.h b/arch/loongarch/include/asm/kvm_para.h
>> new file mode 100644
>> index 000000000000..9425d3b7e486
>> --- /dev/null
>> +++ b/arch/loongarch/include/asm/kvm_para.h
>> @@ -0,0 +1,26 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +#ifndef _ASM_LOONGARCH_KVM_PARA_H
>> +#define _ASM_LOONGARCH_KVM_PARA_H
>> +
>> +/*
>> + * LoongArch hypcall return code
> Maybe using "hypercall" in comments is better.
will modify in next patch.

> 
>> + */
>> +#define KVM_HC_STATUS_SUCCESS          0
>> +#define KVM_HC_INVALID_CODE            -1UL
>> +#define KVM_HC_INVALID_PARAMETER       -2UL
> Maybe KVM_HCALL_SUCCESS/KVM_HCALL_INVALID_CODE/KVM_HCALL_PARAMETER is better.
yes, KVM_HCALL_xxxx sounds better. Will modify it.

Regards
Bibo Mao
> 
> Huacai
> 
>> +
>> +static inline unsigned int kvm_arch_para_features(void)
>> +{
>> +       return 0;
>> +}
>> +
>> +static inline unsigned int kvm_arch_para_hints(void)
>> +{
>> +       return 0;
>> +}
>> +
>> +static inline bool kvm_check_and_clear_guest_paused(void)
>> +{
>> +       return false;
>> +}
>> +#endif /* _ASM_LOONGARCH_KVM_PARA_H */
>> diff --git a/arch/loongarch/include/uapi/asm/Kbuild b/arch/loongarch/include/uapi/asm/Kbuild
>> deleted file mode 100644
>> index 4aa680ca2e5f..000000000000
>> --- a/arch/loongarch/include/uapi/asm/Kbuild
>> +++ /dev/null
>> @@ -1,2 +0,0 @@
>> -# SPDX-License-Identifier: GPL-2.0
>> -generic-y += kvm_para.h
>> diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c
>> index ed1d89d53e2e..d15c71320a11 100644
>> --- a/arch/loongarch/kvm/exit.c
>> +++ b/arch/loongarch/kvm/exit.c
>> @@ -685,6 +685,15 @@ static int kvm_handle_lasx_disabled(struct kvm_vcpu *vcpu)
>>          return RESUME_GUEST;
>>   }
>>
>> +static int kvm_handle_hypcall(struct kvm_vcpu *vcpu)
>> +{
>> +       update_pc(&vcpu->arch);
>> +
>> +       /* Treat it as noop intruction, only set return value */
>> +       vcpu->arch.gprs[LOONGARCH_GPR_A0] = KVM_HC_INVALID_CODE;
>> +       return RESUME_GUEST;
>> +}
>> +
>>   /*
>>    * LoongArch KVM callback handling for unimplemented guest exiting
>>    */
>> @@ -716,6 +725,7 @@ static exit_handle_fn kvm_fault_tables[EXCCODE_INT_START] = {
>>          [EXCCODE_LSXDIS]                = kvm_handle_lsx_disabled,
>>          [EXCCODE_LASXDIS]               = kvm_handle_lasx_disabled,
>>          [EXCCODE_GSPR]                  = kvm_handle_gspr,
>> +       [EXCCODE_HVC]                   = kvm_handle_hypcall,
>>   };
>>
>>   int kvm_handle_fault(struct kvm_vcpu *vcpu, int fault)
>> --
>> 2.39.3
>>
diff mbox series

Patch

diff --git a/arch/loongarch/include/asm/Kbuild b/arch/loongarch/include/asm/Kbuild
index 93783fa24f6e..22991a6f0e2b 100644
--- a/arch/loongarch/include/asm/Kbuild
+++ b/arch/loongarch/include/asm/Kbuild
@@ -23,4 +23,3 @@  generic-y += poll.h
 generic-y += param.h
 generic-y += posix_types.h
 generic-y += resource.h
-generic-y += kvm_para.h
diff --git a/arch/loongarch/include/asm/kvm_para.h b/arch/loongarch/include/asm/kvm_para.h
new file mode 100644
index 000000000000..9425d3b7e486
--- /dev/null
+++ b/arch/loongarch/include/asm/kvm_para.h
@@ -0,0 +1,26 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_LOONGARCH_KVM_PARA_H
+#define _ASM_LOONGARCH_KVM_PARA_H
+
+/*
+ * LoongArch hypcall return code
+ */
+#define KVM_HC_STATUS_SUCCESS		0
+#define KVM_HC_INVALID_CODE		-1UL
+#define KVM_HC_INVALID_PARAMETER	-2UL
+
+static inline unsigned int kvm_arch_para_features(void)
+{
+	return 0;
+}
+
+static inline unsigned int kvm_arch_para_hints(void)
+{
+	return 0;
+}
+
+static inline bool kvm_check_and_clear_guest_paused(void)
+{
+	return false;
+}
+#endif /* _ASM_LOONGARCH_KVM_PARA_H */
diff --git a/arch/loongarch/include/uapi/asm/Kbuild b/arch/loongarch/include/uapi/asm/Kbuild
deleted file mode 100644
index 4aa680ca2e5f..000000000000
--- a/arch/loongarch/include/uapi/asm/Kbuild
+++ /dev/null
@@ -1,2 +0,0 @@ 
-# SPDX-License-Identifier: GPL-2.0
-generic-y += kvm_para.h
diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c
index ed1d89d53e2e..d15c71320a11 100644
--- a/arch/loongarch/kvm/exit.c
+++ b/arch/loongarch/kvm/exit.c
@@ -685,6 +685,15 @@  static int kvm_handle_lasx_disabled(struct kvm_vcpu *vcpu)
 	return RESUME_GUEST;
 }
 
+static int kvm_handle_hypcall(struct kvm_vcpu *vcpu)
+{
+	update_pc(&vcpu->arch);
+
+	/* Treat it as noop intruction, only set return value */
+	vcpu->arch.gprs[LOONGARCH_GPR_A0] = KVM_HC_INVALID_CODE;
+	return RESUME_GUEST;
+}
+
 /*
  * LoongArch KVM callback handling for unimplemented guest exiting
  */
@@ -716,6 +725,7 @@  static exit_handle_fn kvm_fault_tables[EXCCODE_INT_START] = {
 	[EXCCODE_LSXDIS]		= kvm_handle_lsx_disabled,
 	[EXCCODE_LASXDIS]		= kvm_handle_lasx_disabled,
 	[EXCCODE_GSPR]			= kvm_handle_gspr,
+	[EXCCODE_HVC]			= kvm_handle_hypcall,
 };
 
 int kvm_handle_fault(struct kvm_vcpu *vcpu, int fault)