[PATCH 02/15] arm64: KVM: Kill HYP_PAGE_OFFSET

Marc Zyngier
2016-06-07T10:58:47Z

HYP_PAGE_OFFSET is not massively useful. And the way we use it
in KERN_HYP_VA is inconsistent with the equivalent operation in
EL2, where we use a mask instead.

Let's replace the uses of HYP_PAGE_OFFSET with HYP_PAGE_OFFSET_MASK,
and get rid of the pointless macro.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
arch/arm64/include/asm/kvm_hyp.h | 5 ++---
arch/arm64/include/asm/kvm_mmu.h | 3 +--
2 files changed, 3 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h
index 44eaff7..61d01a9 100644
--- a/arch/arm64/include/asm/kvm_hyp.h
+++ b/arch/arm64/include/asm/kvm_hyp.h
@@ -38,11 +38,10 @@ static inline unsigned long __kern_hyp_va(unsigned long v)

static inline unsigned long __hyp_kern_va(unsigned long v)
{
- u64 offset = PAGE_OFFSET - HYP_PAGE_OFFSET;
- asm volatile(ALTERNATIVE("add %0, %0, %1",
+ asm volatile(ALTERNATIVE("orr %0, %0, %1",
"nop",
ARM64_HAS_VIRT_HOST_EXTN)
- : "+r" (v) : "r" (offset));
+ : "+r" (v) : "i" (~HYP_PAGE_OFFSET_MASK));
return v;
}

diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h
index 00bc277..d162372 100644
--- a/arch/arm64/include/asm/kvm_mmu.h
+++ b/arch/arm64/include/asm/kvm_mmu.h
@@ -75,7 +75,6 @@
*/
#define HYP_PAGE_OFFSET_SHIFT VA_BITS
#define HYP_PAGE_OFFSET_MASK ((UL(1) << HYP_PAGE_OFFSET_SHIFT) - 1)
-#define HYP_PAGE_OFFSET (PAGE_OFFSET & HYP_PAGE_OFFSET_MASK)

/*
* Our virtual mapping for the idmap-ed MMU-enable code. Must be
@@ -109,7 +108,7 @@ alternative_endif
#include <asm/mmu_context.h>
#include <asm/pgtable.h>

-#define KERN_TO_HYP(kva) ((unsigned long)kva - PAGE_OFFSET + HYP_PAGE_OFFSET)
+#define KERN_TO_HYP(kva) ((unsigned long)kva & HYP_PAGE_OFFSET_MASK)

/*
* We currently only support a 40bit IPA.
--
2.1.4