[PATCH v4 7/8] KVM: x86: hyperv: simplistic HVCALL_FLUSH_VIRTUAL_ADDRESS_{LIST,SPACE}_EX implementation

Vitaly Kuznetsov
2018-05-16T15:22:17Z

Implement HvFlushVirtualAddress{List,Space}Ex hypercalls in the same way
we've implemented non-EX counterparts.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
arch/x86/kvm/hyperv.c | 110 ++++++++++++++++++++++++++++++++++++++++++++------
arch/x86/kvm/trace.h | 27 +++++++++++++
2 files changed, 125 insertions(+), 12 deletions(-)

diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 0d916606519d..b298391f0f93 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -1242,31 +1242,102 @@ int kvm_hv_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata)
return kvm_hv_get_msr(vcpu, msr, pdata);
}

+static __always_inline int get_sparse_bank_no(u64 valid_bank_mask, int bank_no)
+{
+ int i = 0, j;
+
+ if (!(valid_bank_mask & BIT_ULL(bank_no)))
+ return -1;
+
+ for (j = 0; j < bank_no; j++)
+ if (valid_bank_mask & BIT_ULL(j))
+ i++;
+
+ return i;
+}
+
static u64 kvm_hv_flush_tlb(struct kvm_vcpu *current_vcpu, u64 ingpa,
- u16 rep_cnt)
+ u16 rep_cnt, bool ex)
{
struct kvm *kvm = current_vcpu->kvm;
struct kvm_vcpu_hv *hv_current = &current_vcpu->arch.hyperv;
+ struct hv_tlb_flush_ex flush_ex;
struct hv_tlb_flush flush;
struct kvm_vcpu *vcpu;
unsigned long vcpu_bitmap[BITS_TO_LONGS(KVM_MAX_VCPUS)] = {0};
- int i;
+ unsigned long valid_bank_mask;
+ u64 sparse_banks[64];
+ int sparse_banks_len, i;
+ bool all_cpus;

- if (unlikely(kvm_read_guest(kvm, ingpa, &flush, sizeof(flush))))
- return HV_STATUS_INVALID_HYPERCALL_INPUT;
+ if (!ex) {
+ if (unlikely(kvm_read_guest(kvm, ingpa, &flush, sizeof(flush))))
+ return HV_STATUS_INVALID_HYPERCALL_INPUT;

- trace_kvm_hv_flush_tlb(flush.processor_mask, flush.address_space,
- flush.flags);
+ trace_kvm_hv_flush_tlb(flush.processor_mask,
+ flush.address_space, flush.flags);
+
+ sparse_banks[0] = flush.processor_mask;
+ all_cpus = flush.flags & HV_FLUSH_ALL_PROCESSORS;
+ } else {
+ if (unlikely(kvm_read_guest(kvm, ingpa, &flush_ex,
+ sizeof(flush_ex))))
+ return HV_STATUS_INVALID_HYPERCALL_INPUT;
+
+ trace_kvm_hv_flush_tlb_ex(flush_ex.hv_vp_set.valid_bank_mask,
+ flush_ex.hv_vp_set.format,
+ flush_ex.address_space,
+ flush_ex.flags);
+
+ valid_bank_mask = flush_ex.hv_vp_set.valid_bank_mask;
+ all_cpus = flush_ex.hv_vp_set.format !=
+ HV_GENERIC_SET_SPARSE_4K;
+
+ sparse_banks_len = bitmap_weight(&valid_bank_mask, 64) *
+ sizeof(sparse_banks[0]);
+
+ if (!sparse_banks_len && !all_cpus)
+ goto ret_success;
+
+ if (!all_cpus &&
+ kvm_read_guest(kvm,
+ ingpa + offsetof(struct hv_tlb_flush_ex,
+ hv_vp_set.bank_contents),
+ sparse_banks,
+ sparse_banks_len))
+ return HV_STATUS_INVALID_HYPERCALL_INPUT;
+ }

cpumask_clear(&hv_current->tlb_lush);

kvm_for_each_vcpu(i, vcpu, kvm) {
struct kvm_vcpu_hv *hv = &vcpu->arch.hyperv;
+ int bank = hv->vp_index / 64, sbank = 0;
+
+ if (!all_cpus) {
+ /* Banks >64 can't be represented */
+ if (bank >= 64)
+ continue;
+
+ /* Non-ex hypercalls can only address first 64 vCPUs */
+ if (!ex && bank)
+ continue;
+
+ if (ex) {
+ /*
+ * Check is the bank of this vCPU is in sparse
+ * set and get the sparse bank number.
+ */
+ sbank = get_sparse_bank_no(valid_bank_mask,
+ bank);
+
+ if (sbank < 0)
+ continue;
+ }

- if (!(flush.flags & HV_FLUSH_ALL_PROCESSORS) &&
- (hv->vp_index >= 64 ||
- !(flush.processor_mask & BIT_ULL(hv->vp_index))))
- continue;
+ if (!(sparse_banks[sbank] & BIT_ULL(hv->vp_index % 64)))
+ continue;
+ }

/*
* vcpu->arch.cr3 may not be up-to-date for running vCPUs so we
@@ -1280,6 +1351,7 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *current_vcpu, u64 ingpa,
KVM_REQ_TLB_FLUSH | KVM_REQUEST_NO_WAKEUP,
vcpu_bitmap, &hv_current->tlb_lush);

+ret_success:
/* We always do full TLB flush, set rep_done = rep_cnt. */
return (u64)HV_STATUS_SUCCESS |
((u64)rep_cnt << HV_HYPERCALL_REP_COMP_OFFSET);
@@ -1427,14 +1499,28 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
break;
}
- ret = kvm_hv_flush_tlb(vcpu, ingpa, rep_cnt);
+ ret = kvm_hv_flush_tlb(vcpu, ingpa, rep_cnt, false);
break;
case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
if (unlikely(fast || rep)) {
ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
break;
}
- ret = kvm_hv_flush_tlb(vcpu, ingpa, rep_cnt);
+ ret = kvm_hv_flush_tlb(vcpu, ingpa, rep_cnt, false);
+ break;
+ case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
+ if (unlikely(fast || !rep_cnt || rep_idx)) {
+ ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
+ break;
+ }
+ ret = kvm_hv_flush_tlb(vcpu, ingpa, rep_cnt, true);
+ break;
+ case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
+ if (unlikely(fast || rep)) {
+ ret = HV_STATUS_INVALID_HYPERCALL_INPUT;
+ break;
+ }
+ ret = kvm_hv_flush_tlb(vcpu, ingpa, rep_cnt, true);
break;
default:
ret = HV_STATUS_INVALID_HYPERCALL_CODE;
diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h
index 47a4fd758743..0f997683404f 100644
--- a/arch/x86/kvm/trace.h
+++ b/arch/x86/kvm/trace.h
@@ -1391,6 +1391,33 @@ TRACE_EVENT(kvm_hv_flush_tlb,
__entry->processor_mask, __entry->address_space,
__entry->flags)
);
+
+/*
+ * Tracepoint for kvm_hv_flush_tlb_ex.
+ */
+TRACE_EVENT(kvm_hv_flush_tlb_ex,
+ TP_PROTO(u64 valid_bank_mask, u64 format, u64 address_space, u64 flags),
+ TP_ARGS(valid_bank_mask, format, address_space, flags),
+
+ TP_STRUCT__entry(
+ __field(u64, valid_bank_mask)
+ __field(u64, format)
+ __field(u64, address_space)
+ __field(u64, flags)
+ ),
+
+ TP_fast_assign(
+ __entry->valid_bank_mask = valid_bank_mask;
+ __entry->format = format;
+ __entry->address_space = address_space;
+ __entry->flags = flags;
+ ),
+
+ TP_printk("valid_bank_mask 0x%llx format 0x%llx "
+ "address_space 0x%llx flags 0x%llx",
+ __entry->valid_bank_mask, __entry->format,
+ __entry->address_space, __entry->flags)
+);
#endif /* _TRACE_KVM_H */

#undef TRACE_INCLUDE_PATH
--
2.14.3