[RFC PATCH v1 20/30] KVM: arm64: add __hyp_running_ctxt and __hyp_running_hyps

[Fuad Tabba]

In order to prepare to remove __hyp_running_vcpu, add
__hyp_running_ctxt and __hyp_running_hyps to access the running
kvm_cpu_ctxt and the hyp_state, as well as their associated
assembly offsets.

These new fields are updated but not accessed yet. Their state is
consistent with __hyp_running_vcpu.

Signed-off-by: Fuad Tabba <tabba at google.com>
---
 arch/arm64/include/asm/kvm_asm.h  | 13 +++++++++++++
 arch/arm64/include/asm/kvm_host.h | 19 ++++++++++++++++---
 arch/arm64/kernel/asm-offsets.c   |  2 ++
 arch/arm64/kvm/hyp/entry.S        |  2 +-
 4 files changed, 32 insertions(+), 4 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
index 766b6a852407..52079e937fcd 100644
--- a/arch/arm64/include/asm/kvm_asm.h
+++ b/arch/arm64/include/asm/kvm_asm.h
@@ -271,6 +271,19 @@ extern u32 __kvm_get_mdcr_el2(void);
 .macro set_loaded_vcpu vcpu, ctxt, tmp
 	adr_this_cpu \ctxt, kvm_hyp_ctxt, \tmp
 	str	\vcpu, [\ctxt, #HOST_CONTEXT_VCPU]
+
+	add	\tmp, \vcpu, #VCPU_CONTEXT
+	str	\tmp, [\ctxt, #HOST_CONTEXT_CTXT]
+
+	add	\tmp, \vcpu, #VCPU_HYPS
+	str	\tmp, [\ctxt, #HOST_CONTEXT_HYPS]
+.endm
+
+.macro clear_loaded_vcpu ctxt, tmp
+	adr_this_cpu \ctxt, kvm_hyp_ctxt, \tmp
+	str	xzr, [\ctxt, #HOST_CONTEXT_VCPU]
+	str	xzr, [\ctxt, #HOST_CONTEXT_CTXT]
+	str	xzr, [\ctxt, #HOST_CONTEXT_HYPS]
 .endm
 
 .macro get_loaded_vcpu_ctxt vcpu, ctxt
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 4b01c74705ad..b42d0c6c8004 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -228,14 +228,27 @@ struct kvm_cpu_context {
 	u64 sys_regs[NR_SYS_REGS];
 
 	struct kvm_vcpu *__hyp_running_vcpu;
+	struct kvm_cpu_context *__hyp_running_ctxt;
+	struct vcpu_hyp_state *__hyp_running_hyps;
 };
 
 #define get_hyp_running_vcpu(ctxt) (ctxt)->__hyp_running_vcpu
-#define set_hyp_running_vcpu(ctxt, vcpu) (ctxt)->__hyp_running_vcpu = (vcpu)
+#define set_hyp_running_vcpu(host_ctxt, vcpu) do { \
+	struct kvm_vcpu *v = (vcpu); \
+	(host_ctxt)->__hyp_running_vcpu = v; \
+	if (vcpu) { \
+		(host_ctxt)->__hyp_running_ctxt = &v->arch.ctxt; \
+		(host_ctxt)->__hyp_running_hyps = &v->arch.hyp_state; \
+	} else { \
+		(host_ctxt)->__hyp_running_ctxt = NULL; \
+		(host_ctxt)->__hyp_running_hyps = NULL;	\
+	}\
+} while(0)
+
 #define is_hyp_running_vcpu(ctxt) (ctxt)->__hyp_running_vcpu
 
-#define get_hyp_running_ctxt(host_ctxt) (host_ctxt)->__hyp_running_vcpu ? &(host_ctxt)->__hyp_running_vcpu->arch.ctxt : NULL
-#define get_hyp_running_hyps(host_ctxt) (host_ctxt)->__hyp_running_vcpu ? &(host_ctxt)->__hyp_running_vcpu->arch.hyp_state : NULL
+#define get_hyp_running_ctxt(host_ctxt) (host_ctxt)->__hyp_running_ctxt
+#define get_hyp_running_hyps(host_ctxt) (host_ctxt)->__hyp_running_hyps
 
 struct kvm_pmu_events {
 	u32 events_host;
diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c
index 1ecc55570acc..9c25078da294 100644
--- a/arch/arm64/kernel/asm-offsets.c
+++ b/arch/arm64/kernel/asm-offsets.c
@@ -117,6 +117,8 @@ int main(void)
   DEFINE(CPU_APDBKEYLO_EL1,	offsetof(struct kvm_cpu_context, sys_regs[APDBKEYLO_EL1]));
   DEFINE(CPU_APGAKEYLO_EL1,	offsetof(struct kvm_cpu_context, sys_regs[APGAKEYLO_EL1]));
   DEFINE(HOST_CONTEXT_VCPU,	offsetof(struct kvm_cpu_context, __hyp_running_vcpu));
+  DEFINE(HOST_CONTEXT_CTXT,	offsetof(struct kvm_cpu_context, __hyp_running_ctxt));
+  DEFINE(HOST_CONTEXT_HYPS,	offsetof(struct kvm_cpu_context, __hyp_running_hyps));
   DEFINE(HOST_DATA_CONTEXT,	offsetof(struct kvm_host_data, host_ctxt));
   DEFINE(NVHE_INIT_MAIR_EL2,	offsetof(struct kvm_nvhe_init_params, mair_el2));
   DEFINE(NVHE_INIT_TCR_EL2,	offsetof(struct kvm_nvhe_init_params, tcr_el2));
diff --git a/arch/arm64/kvm/hyp/entry.S b/arch/arm64/kvm/hyp/entry.S
index 1804be5b7ead..8e7033aa5770 100644
--- a/arch/arm64/kvm/hyp/entry.S
+++ b/arch/arm64/kvm/hyp/entry.S
@@ -145,7 +145,7 @@ SYM_INNER_LABEL(__guest_exit, SYM_L_GLOBAL)
 	// Now restore the hyp regs
 	restore_callee_saved_regs x2
 
-	set_loaded_vcpu xzr, x2, x3
+	clear_loaded_vcpu x2, x3
 
 alternative_if ARM64_HAS_RAS_EXTN
 	// If we have the RAS extensions we can consume a pending error
-- 
2.33.0.685.g46640cef36-goog