KVM: x86/mmu: Track write/user faults using bools

Use bools to track write and user faults throughout the page fault paths
and down into mmu_set_spte().  The actual usage is purely boolean, but
that's not obvious without digging into all paths as the current code
uses a mix of bools (TDP and try_async_pf) and ints (shadow paging and
mmu_set_spte()).

No true functional change intended (although the pgprintk() will now
print 0/1 instead of 0/PFERR_WRITE_MASK).

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200923183735.584-9-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index ae47a0a..d58658d 100644 (file)
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -3082,7 +3082,7 @@ set_pte:
 }
 
 static int mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
-                       unsigned int pte_access, int write_fault, int level,
+                       unsigned int pte_access, bool write_fault, int level,
                        gfn_t gfn, kvm_pfn_t pfn, bool speculative,
                        bool host_writable)
 {
@@ -3188,7 +3188,7 @@ static int direct_pte_prefetch_many(struct kvm_vcpu *vcpu,
                return -1;
 
        for (i = 0; i < ret; i++, gfn++, start++) {
-               mmu_set_spte(vcpu, start, access, 0, sp->role.level, gfn,
+               mmu_set_spte(vcpu, start, access, false, sp->role.level, gfn,
                             page_to_pfn(pages[i]), true, true);
                put_page(pages[i]);
        }

diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h
index 479b65d..9a1a15f 100644 (file)
--- a/arch/x86/kvm/mmu/paging_tmpl.h
+++ b/arch/x86/kvm/mmu/paging_tmpl.h
@@ -550,7 +550,7 @@ FNAME(prefetch_gpte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
         * we call mmu_set_spte() with host_writable = true because
         * pte_prefetch_gfn_to_pfn always gets a writable pfn.
         */
-       mmu_set_spte(vcpu, spte, pte_access, 0, PG_LEVEL_4K, gfn, pfn,
+       mmu_set_spte(vcpu, spte, pte_access, false, PG_LEVEL_4K, gfn, pfn,
                     true, true);
 
        kvm_release_pfn_clean(pfn);
@@ -630,7 +630,7 @@ static int FNAME(fetch)(struct kvm_vcpu *vcpu, gpa_t addr,
                         bool prefault)
 {
        bool nx_huge_page_workaround_enabled = is_nx_huge_page_enabled();
-       int write_fault = error_code & PFERR_WRITE_MASK;
+       bool write_fault = error_code & PFERR_WRITE_MASK;
        bool exec = error_code & PFERR_FETCH_MASK;
        bool huge_page_disallowed = exec && nx_huge_page_workaround_enabled;
        struct kvm_mmu_page *sp = NULL;
@@ -746,7 +746,7 @@ out_gpte_changed:
  */
 static bool
 FNAME(is_self_change_mapping)(struct kvm_vcpu *vcpu,
-                             struct guest_walker *walker, int user_fault,
+                             struct guest_walker *walker, bool user_fault,
                              bool *write_fault_to_shadow_pgtable)
 {
        int level;
@@ -784,8 +784,8 @@ FNAME(is_self_change_mapping)(struct kvm_vcpu *vcpu,
 static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gpa_t addr, u32 error_code,
                             bool prefault)
 {
-       int write_fault = error_code & PFERR_WRITE_MASK;
-       int user_fault = error_code & PFERR_USER_MASK;
+       bool write_fault = error_code & PFERR_WRITE_MASK;
+       bool user_fault = error_code & PFERR_USER_MASK;
        struct guest_walker walker;
        int r;
        kvm_pfn_t pfn;