[RFC 2/6] KVM: arm64: Add SMCCC paravirtualised lock calls

[Usama Arif]

Add two new SMCCC compatible hypercalls for PV lock features:
  PV_LOCK_FEATURES:   0xC6000020
  PV_LOCK_PREEMPTED:  0xC6000021

Also add the header file which defines the ABI for the paravirtualized
lock features we're about to add.

Signed-off-by: Zengruan Ye <yezengruan@xxxxxxxxxx>
Signed-off-by: Usama Arif <usama.arif@xxxxxxxxxxxxx>
---
 arch/arm64/include/asm/pvlock-abi.h | 17 +++++++++++++++++
 include/linux/arm-smccc.h           | 13 +++++++++++++
 2 files changed, 30 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 <yezengruan@xxxxxxxxxx>
+ *         Usama Arif <usama.arif@xxxxxxxxxxxxx>
+ */
+
+#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..6360333e0f64 100644
--- a/include/linux/arm-smccc.h
+++ b/include/linux/arm-smccc.h
@@ -151,6 +151,19 @@
 			   ARM_SMCCC_OWNER_STANDARD_HYP,	\
 			   0x21)
 
+/* Paravirtualised lock calls */
+#define ARM_SMCCC_HV_PV_LOCK_FEATURES				\
+	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,			\
+			   ARM_SMCCC_SMC_64,			\
+			   ARM_SMCCC_OWNER_VENDOR_HYP,		\
+			   0x20)
+
+#define ARM_SMCCC_HV_PV_LOCK_PREEMPTED				\
+	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,			\
+			   ARM_SMCCC_SMC_64,			\
+			   ARM_SMCCC_OWNER_VENDOR_HYP,		\
+			   0x21)
+
 /* TRNG entropy source calls (defined by ARM DEN0098) */
 #define ARM_SMCCC_TRNG_VERSION					\
 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,			\
-- 
2.25.1