[PATCH 3.16 30/72] KVM: mmio: cleanup kvm_set_mmio_spte_mask

Ben Hutchings
2019-12-08T13:58:26Z

From: Tiejun Chen <tiejun.chen@intel.com>

commit d143148383d0395539073dd6c2f25ddf6656bdcc upstream.

Just reuse rsvd_bits() inside kvm_set_mmio_spte_mask()
for slightly better code.

Signed-off-by: Tiejun Chen <tiejun.chen@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[bwh: Backported to 3.16 as dependency of commit 16cfacc80857
"KVM: x86: Manually calculate reserved bits when loading PDPTRS"]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
arch/x86/kvm/mmu.c | 5 -----
arch/x86/kvm/mmu.h | 5 +++++
arch/x86/kvm/x86.c | 2 +-
3 files changed, 6 insertions(+), 6 deletions(-)

--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -295,11 +295,6 @@ static bool check_mmio_spte(struct kvm *
return likely(kvm_gen == spte_gen);
}

-static inline u64 rsvd_bits(int s, int e)
-{
- return ((1ULL << (e - s + 1)) - 1) << s;
-}
-
void kvm_mmu_set_mask_ptes(u64 user_mask, u64 accessed_mask,
u64 dirty_mask, u64 nx_mask, u64 x_mask)
{
--- a/arch/x86/kvm/mmu.h
+++ b/arch/x86/kvm/mmu.h
@@ -56,6 +56,11 @@
#define PFERR_RSVD_MASK (1U << PFERR_RSVD_BIT)
#define PFERR_FETCH_MASK (1U << PFERR_FETCH_BIT)

+static inline u64 rsvd_bits(int s, int e)
+{
+ return ((1ULL << (e - s + 1)) - 1) << s;
+}
+
int kvm_mmu_get_spte_hierarchy(struct kvm_vcpu *vcpu, u64 addr, u64 sptes[4]);
void kvm_mmu_set_mmio_spte_mask(u64 mmio_mask);

--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5689,7 +5689,7 @@ static void kvm_set_mmio_spte_mask(void)
* entry to generate page fault with PFER.RSV = 1.
*/
/* Mask the reserved physical address bits. */
- mask = ((1ull << (51 - maxphyaddr + 1)) - 1) << maxphyaddr;
+ mask = rsvd_bits(maxphyaddr, 51);

/* Bit 62 is always reserved for 32bit host. */
mask |= 0x3ull << 62;