[PATCH v4 12/20] KVM: arm64: Elide kern_hyp_va() in VHE-specific parts of the hypervisor
Marc Zyngier
maz at kernel.org
Thu Mar 30 10:47:52 PDT 2023
For VHE-specific hypervisor code, kern_hyp_va() is a NOP.
Actually, it is a whole range of NOPs. It'd be much better if
this code simply didn't exist. Let's just do that.
Signed-off-by: Marc Zyngier <maz at kernel.org>
---
arch/arm64/include/asm/kvm_mmu.h | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h
index 083cc47dca08..27e63c111f78 100644
--- a/arch/arm64/include/asm/kvm_mmu.h
+++ b/arch/arm64/include/asm/kvm_mmu.h
@@ -63,6 +63,7 @@
* specific registers encoded in the instructions).
*/
.macro kern_hyp_va reg
+#ifndef __KVM_VHE_HYPERVISOR__
alternative_cb ARM64_ALWAYS_SYSTEM, kvm_update_va_mask
and \reg, \reg, #1 /* mask with va_mask */
ror \reg, \reg, #1 /* rotate to the first tag bit */
@@ -70,6 +71,7 @@ alternative_cb ARM64_ALWAYS_SYSTEM, kvm_update_va_mask
add \reg, \reg, #0, lsl 12 /* insert the top 12 bits of the tag */
ror \reg, \reg, #63 /* rotate back */
alternative_cb_end
+#endif
.endm
/*
@@ -127,6 +129,7 @@ void kvm_apply_hyp_relocations(void);
static __always_inline unsigned long __kern_hyp_va(unsigned long v)
{
+#ifndef __KVM_VHE_HYPERVISOR__
asm volatile(ALTERNATIVE_CB("and %0, %0, #1\n"
"ror %0, %0, #1\n"
"add %0, %0, #0\n"
@@ -135,6 +138,7 @@ static __always_inline unsigned long __kern_hyp_va(unsigned long v)
ARM64_ALWAYS_SYSTEM,
kvm_update_va_mask)
: "+r" (v));
+#endif
return v;
}
--
2.34.1
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