Commit 1a6511eb authored by Marc Zyngier's avatar Marc Zyngier
Browse files

KVM: arm64: Elide kern_hyp_va() in VHE-specific parts of the hypervisor 



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: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230330174800.2677007-13-maz@kernel.org
parent 8a5eb2d2

arch/arm64/include/asm/kvm_mmu.h

+4 −0
Original line number Diff line number Diff line
@@ -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;

}