[PATCH v3 4/8] KVM: x86: Add a helper to get the sparse VP_SET for IPIs and TLB flushes
From: Sean Christopherson <seanjc@google.com>
Date: 2021-12-07 22:09:52
Also in:
kvm, linux-hyperv, lkml
Subsystem:
kernel virtual machine for x86 (kvm/x86), kvm x86 hyper-v (kvm/hyper-v), the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Sean Christopherson, Paolo Bonzini, Vitaly Kuznetsov, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
Add a helper, kvm_get_sparse_vp_set(), to handle sanity checks related to the VARHEAD field and reading the sparse banks of a VP_SET. A future commit to reduce the memory footprint of sparse_banks will introduce more common code to the sparse bank retrieval. No functional change intended. Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> --- arch/x86/kvm/hyperv.c | 32 ++++++++++++++++---------------- 1 file changed, 16 insertions(+), 16 deletions(-)
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 9bc856370a2d..680ba3d5d2ad 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c@@ -1751,10 +1751,19 @@ struct kvm_hv_hcall { sse128_t xmm[HV_HYPERCALL_MAX_XMM_REGISTERS]; }; +static u64 kvm_get_sparse_vp_set(struct kvm *kvm, struct kvm_hv_hcall *hc, + u64 *sparse_banks, gpa_t offset) +{ + if (hc->var_cnt > 64) + return -EINVAL; + + return kvm_read_guest(kvm, hc->ingpa + offset, sparse_banks, + hc->var_cnt * sizeof(*sparse_banks)); +} + static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool ex) { int i; - gpa_t gpa; struct kvm *kvm = vcpu->kvm; struct hv_tlb_flush_ex flush_ex; struct hv_tlb_flush flush;
@@ -1831,13 +1840,9 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool goto do_flush; } - if (hc->var_cnt > 64) - return HV_STATUS_INVALID_HYPERCALL_INPUT; - - gpa = hc->ingpa + offsetof(struct hv_tlb_flush_ex, - hv_vp_set.bank_contents); - if (unlikely(kvm_read_guest(kvm, gpa, sparse_banks, - hc->var_cnt * sizeof(sparse_banks[0])))) + if (kvm_get_sparse_vp_set(kvm, hc, sparse_banks, + offsetof(struct hv_tlb_flush_ex, + hv_vp_set.bank_contents))) return HV_STATUS_INVALID_HYPERCALL_INPUT; }
@@ -1934,14 +1939,9 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc, bool if (!hc->var_cnt) goto ret_success; - if (hc->var_cnt > 64) - return HV_STATUS_INVALID_HYPERCALL_INPUT; - - if (kvm_read_guest(kvm, - hc->ingpa + offsetof(struct hv_send_ipi_ex, - vp_set.bank_contents), - sparse_banks, - hc->var_cnt * sizeof(sparse_banks[0]))) + if (kvm_get_sparse_vp_set(kvm, hc, sparse_banks, + offsetof(struct hv_send_ipi_ex, + vp_set.bank_contents))) return HV_STATUS_INVALID_HYPERCALL_INPUT; }
--
2.34.1.400.ga245620fadb-goog