[PATCH v3 24/31] KVM: MMU: clean up make_spte return value

From: Paolo Bonzini
Date: Fri Sep 24 2021 - 12:33:09 EST


Now that make_spte is called directly by the shadow MMU (rather than
wrapped by set_spte), it only has to return one boolean value.

Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
arch/x86/kvm/mmu/mmu.c | 8 ++++----
arch/x86/kvm/mmu/mmu_internal.h | 5 -----
arch/x86/kvm/mmu/spte.c | 8 ++++----
arch/x86/kvm/mmu/spte.h | 7 +------
arch/x86/kvm/mmu/tdp_mmu.c | 6 +++---
5 files changed, 12 insertions(+), 22 deletions(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 19c2fd2189a3..dcbe7df2f890 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -2683,7 +2683,7 @@ static int mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
int was_rmapped = 0;
int ret = RET_PF_FIXED;
bool flush = false;
- int make_spte_ret;
+ bool wrprot;
u64 spte;

pgprintk("%s: spte %llx write_fault %d gfn %llx\n", __func__,
@@ -2715,8 +2715,8 @@ static int mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
was_rmapped = 1;
}

- make_spte_ret = make_spte(vcpu, pte_access, level, gfn, pfn, *sptep, speculative,
- true, host_writable, sp_ad_disabled(sp), &spte);
+ wrprot = make_spte(vcpu, pte_access, level, gfn, pfn, *sptep, speculative,
+ true, host_writable, sp_ad_disabled(sp), &spte);

if (*sptep == spte) {
ret = RET_PF_SPURIOUS;
@@ -2725,7 +2725,7 @@ static int mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
flush |= mmu_spte_update(sptep, spte);
}

- if (make_spte_ret & SET_SPTE_WRITE_PROTECTED_PT) {
+ if (wrprot) {
if (write_fault)
ret = RET_PF_EMULATE;
}
diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h
index f0295ad51f69..94f4e754facb 100644
--- a/arch/x86/kvm/mmu/mmu_internal.h
+++ b/arch/x86/kvm/mmu/mmu_internal.h
@@ -150,11 +150,6 @@ enum {
RET_PF_SPURIOUS,
};

-/* Bits which may be returned by set_spte() */
-#define SET_SPTE_WRITE_PROTECTED_PT BIT(0)
-#define SET_SPTE_NEED_REMOTE_TLB_FLUSH BIT(1)
-#define SET_SPTE_SPURIOUS BIT(2)
-
int kvm_mmu_max_mapping_level(struct kvm *kvm,
const struct kvm_memory_slot *slot, gfn_t gfn,
kvm_pfn_t pfn, int max_level);
diff --git a/arch/x86/kvm/mmu/spte.c b/arch/x86/kvm/mmu/spte.c
index 66be9452ded1..29ea996201b4 100644
--- a/arch/x86/kvm/mmu/spte.c
+++ b/arch/x86/kvm/mmu/spte.c
@@ -89,13 +89,13 @@ static bool kvm_is_mmio_pfn(kvm_pfn_t pfn)
E820_TYPE_RAM);
}

-int make_spte(struct kvm_vcpu *vcpu, unsigned int pte_access, int level,
+bool make_spte(struct kvm_vcpu *vcpu, unsigned int pte_access, int level,
gfn_t gfn, kvm_pfn_t pfn, u64 old_spte, bool speculative,
bool can_unsync, bool host_writable, bool ad_disabled,
u64 *new_spte)
{
u64 spte = SPTE_MMU_PRESENT_MASK;
- int ret = 0;
+ bool wrprot = false;

if (ad_disabled)
spte |= SPTE_TDP_AD_DISABLED_MASK;
@@ -162,7 +162,7 @@ int make_spte(struct kvm_vcpu *vcpu, unsigned int pte_access, int level,
if (mmu_try_to_unsync_pages(vcpu, gfn, can_unsync, speculative)) {
pgprintk("%s: found shadow page for %llx, marking ro\n",
__func__, gfn);
- ret |= SET_SPTE_WRITE_PROTECTED_PT;
+ wrprot = true;
pte_access &= ~ACC_WRITE_MASK;
spte &= ~(PT_WRITABLE_MASK | shadow_mmu_writable_mask);
}
@@ -183,7 +183,7 @@ int make_spte(struct kvm_vcpu *vcpu, unsigned int pte_access, int level,
kvm_vcpu_mark_page_dirty(vcpu, gfn);

*new_spte = spte;
- return ret;
+ return wrprot;
}

u64 make_nonleaf_spte(u64 *child_pt, bool ad_disabled)
diff --git a/arch/x86/kvm/mmu/spte.h b/arch/x86/kvm/mmu/spte.h
index eb7b227fc6cf..1998ec559196 100644
--- a/arch/x86/kvm/mmu/spte.h
+++ b/arch/x86/kvm/mmu/spte.h
@@ -334,12 +334,7 @@ static inline u64 get_mmio_spte_generation(u64 spte)
return gen;
}

-/* Bits which may be returned by set_spte() */
-#define SET_SPTE_WRITE_PROTECTED_PT BIT(0)
-#define SET_SPTE_NEED_REMOTE_TLB_FLUSH BIT(1)
-#define SET_SPTE_SPURIOUS BIT(2)
-
-int make_spte(struct kvm_vcpu *vcpu, unsigned int pte_access, int level,
+bool make_spte(struct kvm_vcpu *vcpu, unsigned int pte_access, int level,
gfn_t gfn, kvm_pfn_t pfn, u64 old_spte, bool speculative,
bool can_unsync, bool host_writable, bool ad_disabled,
u64 *new_spte);
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 3e10658cf0d7..6de2c957edd6 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -898,12 +898,12 @@ static int tdp_mmu_map_handle_target_level(struct kvm_vcpu *vcpu,
{
u64 new_spte;
int ret = RET_PF_FIXED;
- int make_spte_ret = 0;
+ bool wrprot = false;

if (unlikely(!fault->slot))
new_spte = make_mmio_spte(vcpu, iter->gfn, ACC_ALL);
else
- make_spte_ret = make_spte(vcpu, ACC_ALL, iter->level, iter->gfn,
+ wrprot = make_spte(vcpu, ACC_ALL, iter->level, iter->gfn,
fault->pfn, iter->old_spte, fault->prefault, true,
fault->map_writable, !shadow_accessed_mask,
&new_spte);
@@ -918,7 +918,7 @@ static int tdp_mmu_map_handle_target_level(struct kvm_vcpu *vcpu,
* protected, emulation is needed. If the emulation was skipped,
* the vCPU would have the same fault again.
*/
- if (make_spte_ret & SET_SPTE_WRITE_PROTECTED_PT) {
+ if (wrprot) {
if (fault->write)
ret = RET_PF_EMULATE;
}
--
2.27.0