As we're moving towards a much more dynamic way to compute our
HYP VA, let's express the mask in a slightly different way.
Instead of comparing the idmap position to the "low" VA mask,
we directly compute the mask by taking into account the idmap's
(VA_BIT-1) bit.
No functionnal change.
Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx>
Reviewed-by: Christoffer Dall <christoffer.dall@xxxxxxxxxx>
Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
---
arch/arm64/kvm/va_layout.c | 17 ++++++-----------
1 file changed, 6 insertions(+), 11 deletions(-)
diff --git a/arch/arm64/kvm/va_layout.c b/arch/arm64/kvm/va_layout.c
index 0d7bf8319894..7998d1a60916 100644
--- a/arch/arm64/kvm/va_layout.c
+++ b/arch/arm64/kvm/va_layout.c
@@ -21,24 +21,19 @@
#include <asm/insn.h>
#include <asm/kvm_mmu.h>
-#define HYP_PAGE_OFFSET_HIGH_MASK ((UL(1) << VA_BITS) - 1)
-#define HYP_PAGE_OFFSET_LOW_MASK ((UL(1) << (VA_BITS - 1)) - 1)
-
static u64 va_mask;
static void compute_layout(void)
{
phys_addr_t idmap_addr = __pa_symbol(__hyp_idmap_text_start);
- unsigned long mask = HYP_PAGE_OFFSET_HIGH_MASK;
+ u64 hyp_va_msb;
- /*
- * Activate the lower HYP offset only if the idmap doesn't
- * clash with it,
- */
- if (idmap_addr > HYP_PAGE_OFFSET_LOW_MASK)
- mask = HYP_PAGE_OFFSET_LOW_MASK;
+ /* Where is my RAM region? */
+ hyp_va_msb = idmap_addr & BIT(VA_BITS - 1);
+ hyp_va_msb ^= BIT(VA_BITS - 1);
- va_mask = mask;
+ va_mask = GENMASK_ULL(VA_BITS - 2, 0);
+ va_mask |= hyp_va_msb;
}
static u32 compute_instruction(int n, u32 rd, u32 rn)
--
2.14.2
_______________________________________________
kvmarm mailing list
kvmarm@xxxxxxxxxxxxxxxxxxxxx
https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
