KVM: x86: hyperv: simplistic HVCALL_FLUSH_VIRTUAL_ADDRESS_{LIST,SPACE}_EX implementation

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

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
[Initialized valid_bank_mask to silence misguided GCC warnigs. - Radim]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>

2 files changed, 125 insertions, 12 deletions

diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 0d916606519d..14e0d0ae4e0a 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 = 0;
+        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