KVM: MMU: Introduce struct kvm_page_fault

Create a single structure for arguments that are passed from
kvm_mmu_do_page_fault to the page fault handlers.  Later
the structure will grow to include various output parameters
that are passed back to the next steps in the page fault
handling.

Suggested-by: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h
index e9688a9f7b579d521caeee89017d9b557397c652..0553ef92946e6fc514f9c42ebd9de09398239b39 100644 (file)
--- a/arch/x86/kvm/mmu.h
+++ b/arch/x86/kvm/mmu.h
@@ -114,17 +114,45 @@ static inline void kvm_mmu_load_pgd(struct kvm_vcpu *vcpu)
                                          vcpu->arch.mmu->shadow_root_level);
 }
 
+struct kvm_page_fault {
+       /* arguments to kvm_mmu_do_page_fault.  */
+       const gpa_t addr;
+       const u32 error_code;
+       const bool prefault;
+
+       /* Derived from error_code.  */
+       const bool exec;
+       const bool write;
+       const bool present;
+       const bool rsvd;
+       const bool user;
+
+       /* Derived from mmu.  */
+       const bool is_tdp;
+};
+
 int kvm_tdp_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code,
                       bool prefault);
 
 static inline int kvm_mmu_do_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
                                        u32 err, bool prefault)
 {
+       struct kvm_page_fault fault = {
+               .addr = cr2_or_gpa,
+               .error_code = err,
+               .exec = err & PFERR_FETCH_MASK,
+               .write = err & PFERR_WRITE_MASK,
+               .present = err & PFERR_PRESENT_MASK,
+               .rsvd = err & PFERR_RSVD_MASK,
+               .user = err & PFERR_USER_MASK,
+               .prefault = prefault,
+               .is_tdp = likely(vcpu->arch.mmu->page_fault == kvm_tdp_page_fault),
+       };
 #ifdef CONFIG_RETPOLINE
-       if (likely(vcpu->arch.mmu->page_fault == kvm_tdp_page_fault))
-               return kvm_tdp_page_fault(vcpu, cr2_or_gpa, err, prefault);
+       if (fault.is_tdp)
+               return kvm_tdp_page_fault(vcpu, fault.addr, fault.error_code, fault.prefault);
 #endif
-       return vcpu->arch.mmu->page_fault(vcpu, cr2_or_gpa, err, prefault);
+       return vcpu->arch.mmu->page_fault(vcpu, fault.addr, fault.error_code, fault.prefault);
 }
 
 /*