From 18fc7bf8e041272f74a3237b99261d59c3ff0388 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Sat, 5 Jan 2019 15:57:56 +0000 Subject: [PATCH] arm64: KVM: Allow for direct call of HYP functions when using VHE When running VHE, there is no need to jump via some stub to perform a "HYP" function call, as there is a single address space. Let's thus change kvm_call_hyp() and co to perform a direct call in this case. Although this results in a bit of code expansion, it allows the compiler to check for type compatibility, something that we are missing so far. Signed-off-by: Marc Zyngier Acked-by: Christoffer Dall Signed-off-by: Christoffer Dall --- arch/arm64/include/asm/kvm_host.h | 32 ++++++++++++++++++++++++++++++-- 1 file changed, 30 insertions(+), 2 deletions(-) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index e54cb7c..8b7702b 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -370,8 +370,36 @@ void kvm_arm_halt_guest(struct kvm *kvm); void kvm_arm_resume_guest(struct kvm *kvm); u64 __kvm_call_hyp(void *hypfn, ...); -#define kvm_call_hyp(f, ...) __kvm_call_hyp(kvm_ksym_ref(f), ##__VA_ARGS__) -#define kvm_call_hyp_ret(f, ...) kvm_call_hyp(f, ##__VA_ARGS__) + +/* + * The couple of isb() below are there to guarantee the same behaviour + * on VHE as on !VHE, where the eret to EL1 acts as a context + * synchronization event. + */ +#define kvm_call_hyp(f, ...) \ + do { \ + if (has_vhe()) { \ + f(__VA_ARGS__); \ + isb(); \ + } else { \ + __kvm_call_hyp(kvm_ksym_ref(f), ##__VA_ARGS__); \ + } \ + } while(0) + +#define kvm_call_hyp_ret(f, ...) \ + ({ \ + typeof(f(__VA_ARGS__)) ret; \ + \ + if (has_vhe()) { \ + ret = f(__VA_ARGS__); \ + isb(); \ + } else { \ + ret = __kvm_call_hyp(kvm_ksym_ref(f), \ + ##__VA_ARGS__); \ + } \ + \ + ret; \ + }) void force_vm_exit(const cpumask_t *mask); void kvm_mmu_wp_memory_region(struct kvm *kvm, int slot); -- 2.7.4