Commit a0dd008f authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
Browse files

KVM: x86: Add a helper to get the sparse VP_SET for IPIs and TLB flushes 



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: default avatarSean Christopherson <seanjc@google.com>
Reviewed-by: default avatarVitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20211207220926.718794-5-seanjc@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 25af9081

arch/x86/kvm/hyperv.c

+16 −16
Original line number Diff line number Diff line
@@ -1754,10 +1754,19 @@ 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;
@@ -1834,13 +1843,9 @@ 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;

	}
@@ -1937,14 +1942,9 @@ 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;

	}