KVM: x86: Add a helper to check for user interception of KVM hypercalls

Add and use user_exit_on_hypercall() to check if userspace wants to handle
a KVM hypercall instead of open-coding the logic everywhere.

No functional change intended.

Signed-off-by: Binbin Wu <binbin.wu@linux.intel.com>
Reviewed-by: Isaku Yamahata <isaku.yamahata@intel.com>
Reviewed-by: Kai Huang <kai.huang@intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
[sean: squash into one patch, keep explicit KVM_HC_MAP_GPA_RANGE check]
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-ID: <20241128004344.4072099-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 9ffb0fb5aacd393b2d22a2600cd372d9b66a31b3..5eb7a206f405134f17f85b6539ef9354d241a8a8 100644 (file)
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -3627,7 +3627,7 @@ static int snp_begin_psc_msr(struct vcpu_svm *svm, u64 ghcb_msr)
                return 1; /* resume guest */
        }
 
-       if (!(vcpu->kvm->arch.hypercall_exit_enabled & (1 << KVM_HC_MAP_GPA_RANGE))) {
+       if (!user_exit_on_hypercall(vcpu->kvm, KVM_HC_MAP_GPA_RANGE)) {
                set_ghcb_msr(svm, GHCB_MSR_PSC_RESP_ERROR);
                return 1; /* resume guest */
        }
@@ -3717,7 +3717,7 @@ static int snp_begin_psc(struct vcpu_svm *svm, struct psc_buffer *psc)
        bool huge;
        u64 gfn;
 
-       if (!(vcpu->kvm->arch.hypercall_exit_enabled & (1 << KVM_HC_MAP_GPA_RANGE))) {
+       if (!user_exit_on_hypercall(vcpu->kvm, KVM_HC_MAP_GPA_RANGE)) {
                snp_complete_psc(svm, VMGEXIT_PSC_ERROR_GENERIC);
                return 1;
        }

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 615cba6fe46634b5cd35b07e11657b4940820a36..d485a53ac4103de37333eeb906a5e59476475585 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -10041,7 +10041,7 @@ unsigned long __kvm_emulate_hypercall(struct kvm_vcpu *vcpu, unsigned long nr,
                u64 gpa = a0, npages = a1, attrs = a2;
 
                ret = -KVM_ENOSYS;
-               if (!(vcpu->kvm->arch.hypercall_exit_enabled & (1 << KVM_HC_MAP_GPA_RANGE)))
+               if (!user_exit_on_hypercall(vcpu->kvm, KVM_HC_MAP_GPA_RANGE))
                        break;
 
                if (!PAGE_ALIGNED(gpa) || !npages ||

diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index ec623d23d13d2e2db7cdb5d4d8d330a4ae4cfa0c..45dd53284dbde759ee0247d91967063a8901cd21 100644 (file)
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -612,4 +612,9 @@ int kvm_sev_es_string_io(struct kvm_vcpu *vcpu, unsigned int size,
                         unsigned int port, void *data,  unsigned int count,
                         int in);
 
+static inline bool user_exit_on_hypercall(struct kvm *kvm, unsigned long hc_nr)
+{
+       return kvm->arch.hypercall_exit_enabled & BIT(hc_nr);
+}
+
 #endif