arm64: KVM: Allow for direct call of HYP functions when using VHE (18fc7bf8) · Commits · 戴 / test

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 <marc.zyngier@arm.com> Acked-by:

Christoffer Dall <christoffer.dall@arm.com> Signed-off-by:

Christoffer Dall <christoffer.dall@arm.com>

arch/arm64/include/asm/kvm_host.h

+30 −2

Original line number	Diff line number	Diff line
		@@ -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);

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