Add a new SMCCC compatible hypercalls for PV lock features:
ARM_SMCCC_KVM_FUNC_PV_LOCK: 0xC6000002
Also add the header file which defines the ABI for the paravirtualized
lock features we're about to add.
Signed-off-by: Zengruan Ye <[email protected]>
Signed-off-by: Usama Arif <[email protected]>
---
arch/arm64/include/asm/pvlock-abi.h | 17 +++++++++++++++++
include/linux/arm-smccc.h | 8 ++++++++
tools/include/linux/arm-smccc.h | 8 ++++++++
3 files changed, 33 insertions(+)
create mode 100644 arch/arm64/include/asm/pvlock-abi.h
diff --git a/arch/arm64/include/asm/pvlock-abi.h b/arch/arm64/include/asm/pvlock-abi.h
new file mode 100644
index 000000000000..3f4574071679
--- /dev/null
+++ b/arch/arm64/include/asm/pvlock-abi.h
@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright(c) 2019 Huawei Technologies Co., Ltd
+ * Author: Zengruan Ye <[email protected]>
+ * Usama Arif <[email protected]>
+ */
+
+#ifndef __ASM_PVLOCK_ABI_H
+#define __ASM_PVLOCK_ABI_H
+
+struct pvlock_vcpu_state {
+ __le64 preempted;
+ /* Structure must be 64 byte aligned, pad to that size */
+ u8 padding[56];
+} __packed;
+
+#endif
diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h
index 220c8c60e021..104c10035b10 100644
--- a/include/linux/arm-smccc.h
+++ b/include/linux/arm-smccc.h
@@ -112,6 +112,7 @@
/* KVM "vendor specific" services */
#define ARM_SMCCC_KVM_FUNC_FEATURES 0
#define ARM_SMCCC_KVM_FUNC_PTP 1
+#define ARM_SMCCC_KVM_FUNC_PV_LOCK 2
#define ARM_SMCCC_KVM_FUNC_FEATURES_2 127
#define ARM_SMCCC_KVM_NUM_FUNCS 128
@@ -151,6 +152,13 @@
ARM_SMCCC_OWNER_STANDARD_HYP, \
0x21)
+/* Paravirtualised lock calls */
+#define ARM_SMCCC_VENDOR_HYP_KVM_PV_LOCK_FUNC_ID \
+ ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \
+ ARM_SMCCC_SMC_64, \
+ ARM_SMCCC_OWNER_VENDOR_HYP, \
+ ARM_SMCCC_KVM_FUNC_PV_LOCK)
+
/* TRNG entropy source calls (defined by ARM DEN0098) */
#define ARM_SMCCC_TRNG_VERSION \
ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \
diff --git a/tools/include/linux/arm-smccc.h b/tools/include/linux/arm-smccc.h
index 63ce9bebccd3..c21e539c0228 100644
--- a/tools/include/linux/arm-smccc.h
+++ b/tools/include/linux/arm-smccc.h
@@ -111,6 +111,7 @@
/* KVM "vendor specific" services */
#define ARM_SMCCC_KVM_FUNC_FEATURES 0
#define ARM_SMCCC_KVM_FUNC_PTP 1
+#define ARM_SMCCC_KVM_FUNC_PV_LOCK 2
#define ARM_SMCCC_KVM_FUNC_FEATURES_2 127
#define ARM_SMCCC_KVM_NUM_FUNCS 128
@@ -150,6 +151,13 @@
ARM_SMCCC_OWNER_STANDARD_HYP, \
0x21)
+/* Paravirtualised lock calls */
+#define ARM_SMCCC_VENDOR_HYP_KVM_PV_LOCK_FUNC_ID \
+ ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \
+ ARM_SMCCC_SMC_64, \
+ ARM_SMCCC_OWNER_VENDOR_HYP, \
+ ARM_SMCCC_KVM_FUNC_PV_LOCK)
+
/* TRNG entropy source calls (defined by ARM DEN0098) */
#define ARM_SMCCC_TRNG_VERSION \
ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \
--
2.25.1
On 07/11/2022 17:58, Punit Agrawal wrote:
> Usama Arif <[email protected]> writes:
>
>> Add a new SMCCC compatible hypercalls for PV lock features:
>> ARM_SMCCC_KVM_FUNC_PV_LOCK: 0xC6000002
>>
>> Also add the header file which defines the ABI for the paravirtualized
>> lock features we're about to add.
>>
>> Signed-off-by: Zengruan Ye <[email protected]>
>> Signed-off-by: Usama Arif <[email protected]>
>> ---
>> arch/arm64/include/asm/pvlock-abi.h | 17 +++++++++++++++++
>> include/linux/arm-smccc.h | 8 ++++++++
>> tools/include/linux/arm-smccc.h | 8 ++++++++
>> 3 files changed, 33 insertions(+)
>> create mode 100644 arch/arm64/include/asm/pvlock-abi.h
>>
>> diff --git a/arch/arm64/include/asm/pvlock-abi.h b/arch/arm64/include/asm/pvlock-abi.h
>> new file mode 100644
>> index 000000000000..3f4574071679
>> --- /dev/null
>> +++ b/arch/arm64/include/asm/pvlock-abi.h
>> @@ -0,0 +1,17 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +/*
>> + * Copyright(c) 2019 Huawei Technologies Co., Ltd
>> + * Author: Zengruan Ye <[email protected]>
>> + * Usama Arif <[email protected]>
>> + */
>> +
>> +#ifndef __ASM_PVLOCK_ABI_H
>> +#define __ASM_PVLOCK_ABI_H
>> +
>> +struct pvlock_vcpu_state {
>> + __le64 preempted;
>> + /* Structure must be 64 byte aligned, pad to that size */
>> + u8 padding[56];
>> +} __packed;
>
> For structure alignment, I'd have expected to see the use of "aligned"
> attribute. Is there any benefit in using padding to achieve alignment?
>
Just made it consistent with pvclock-abi.h. If its more appropriate, can
change to aligned in next patchset:
diff --git a/arch/arm64/include/asm/pvlock-abi.h
b/arch/arm64/include/asm/pvlock-abi.h
index 3f4574071679..bacec4cb927a 100644
--- a/arch/arm64/include/asm/pvlock-abi.h
+++ b/arch/arm64/include/asm/pvlock-abi.h
@@ -11,7 +11,6 @@
struct pvlock_vcpu_state {
__le64 preempted;
/* Structure must be 64 byte aligned, pad to that size */
- u8 padding[56];
-} __packed;
+} __attribute__((aligned(64)));
> [...]
Usama Arif <[email protected]> writes:
> Add a new SMCCC compatible hypercalls for PV lock features:
> ARM_SMCCC_KVM_FUNC_PV_LOCK: 0xC6000002
>
> Also add the header file which defines the ABI for the paravirtualized
> lock features we're about to add.
>
> Signed-off-by: Zengruan Ye <[email protected]>
> Signed-off-by: Usama Arif <[email protected]>
> ---
> arch/arm64/include/asm/pvlock-abi.h | 17 +++++++++++++++++
> include/linux/arm-smccc.h | 8 ++++++++
> tools/include/linux/arm-smccc.h | 8 ++++++++
> 3 files changed, 33 insertions(+)
> create mode 100644 arch/arm64/include/asm/pvlock-abi.h
>
> diff --git a/arch/arm64/include/asm/pvlock-abi.h b/arch/arm64/include/asm/pvlock-abi.h
> new file mode 100644
> index 000000000000..3f4574071679
> --- /dev/null
> +++ b/arch/arm64/include/asm/pvlock-abi.h
> @@ -0,0 +1,17 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright(c) 2019 Huawei Technologies Co., Ltd
> + * Author: Zengruan Ye <[email protected]>
> + * Usama Arif <[email protected]>
> + */
> +
> +#ifndef __ASM_PVLOCK_ABI_H
> +#define __ASM_PVLOCK_ABI_H
> +
> +struct pvlock_vcpu_state {
> + __le64 preempted;
> + /* Structure must be 64 byte aligned, pad to that size */
> + u8 padding[56];
> +} __packed;
For structure alignment, I'd have expected to see the use of "aligned"
attribute. Is there any benefit in using padding to achieve alignment?
[...]