[RFC 06/33] KVM: x86: hyper-v: Introduce VTL awareness to Hyper-V's PV-IPIs

[Nicolas Saenz Julienne <nsaenz@amazon.com>]

HVCALL_SEND_IPI and HVCALL_SEND_IPI_EX allow targeting specific a
specific VTL. Honour the requests.

Signed-off-by: Nicolas Saenz Julienne <nsaenz@amazon.com>
---
 arch/x86/kvm/hyperv.c             | 24 +++++++++++++++++-------
 arch/x86/kvm/trace.h              | 20 ++++++++++++--------
 include/asm-generic/hyperv-tlfs.h |  6 ++++--
 3 files changed, 33 insertions(+), 17 deletions(-)

diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index d4b1b53ea63d..2cf430f6ddd8 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -2230,7 +2230,7 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
 }
 
 static void kvm_hv_send_ipi_to_many(struct kvm *kvm, u32 vector,
-				    u64 *sparse_banks, u64 valid_bank_mask)
+				    u64 *sparse_banks, u64 valid_bank_mask, int vtl)
 {
 	struct kvm_lapic_irq irq = {
 		.delivery_mode = APIC_DM_FIXED,
@@ -2245,6 +2245,9 @@ static void kvm_hv_send_ipi_to_many(struct kvm *kvm, u32 vector,
 					    valid_bank_mask, sparse_banks))
 			continue;
 
+		if (kvm_hv_get_active_vtl(vcpu) != vtl)
+			continue;
+
 		/* We fail only when APIC is disabled */
 		kvm_apic_set_irq(vcpu, &irq, NULL);
 	}
@@ -2257,13 +2260,19 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
 	struct kvm *kvm = vcpu->kvm;
 	struct hv_send_ipi_ex send_ipi_ex;
 	struct hv_send_ipi send_ipi;
+	union hv_input_vtl *in_vtl;
 	u64 valid_bank_mask;
 	u32 vector;
 	bool all_cpus;
+	u8 vtl;
+
+	/* VTL is at the same offset on both IPI types */
+	in_vtl = &send_ipi.in_vtl;
+	vtl = in_vtl->use_target_vtl ? in_vtl->target_vtl : kvm_hv_get_active_vtl(vcpu);
 
 	if (hc->code == HVCALL_SEND_IPI) {
 		if (!hc->fast) {
-			if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi,
+			if (unlikely(kvm_vcpu_read_guest(vcpu, hc->ingpa, &send_ipi,
 						    sizeof(send_ipi))))
 				return HV_STATUS_INVALID_HYPERCALL_INPUT;
 			sparse_banks[0] = send_ipi.cpu_mask;
@@ -2278,10 +2287,10 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
 		all_cpus = false;
 		valid_bank_mask = BIT_ULL(0);
 
-		trace_kvm_hv_send_ipi(vector, sparse_banks[0]);
+		trace_kvm_hv_send_ipi(vector, sparse_banks[0], vtl);
 	} else {
 		if (!hc->fast) {
-			if (unlikely(kvm_read_guest(kvm, hc->ingpa, &send_ipi_ex,
+			if (unlikely(kvm_vcpu_read_guest(vcpu, hc->ingpa, &send_ipi_ex,
 						    sizeof(send_ipi_ex))))
 				return HV_STATUS_INVALID_HYPERCALL_INPUT;
 		} else {
@@ -2292,7 +2301,8 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
 
 		trace_kvm_hv_send_ipi_ex(send_ipi_ex.vector,
 					 send_ipi_ex.vp_set.format,
-					 send_ipi_ex.vp_set.valid_bank_mask);
+					 send_ipi_ex.vp_set.valid_bank_mask,
+					 vtl);
 
 		vector = send_ipi_ex.vector;
 		valid_bank_mask = send_ipi_ex.vp_set.valid_bank_mask;
@@ -2322,9 +2332,9 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
 		return HV_STATUS_INVALID_HYPERCALL_INPUT;
 
 	if (all_cpus)
-		kvm_hv_send_ipi_to_many(kvm, vector, NULL, 0);
+		kvm_hv_send_ipi_to_many(kvm, vector, NULL, 0, vtl);
 	else
-		kvm_hv_send_ipi_to_many(kvm, vector, sparse_banks, valid_bank_mask);
+		kvm_hv_send_ipi_to_many(kvm, vector, sparse_banks, valid_bank_mask, vtl);
 
 ret_success:
 	return HV_STATUS_SUCCESS;
diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h
index 83843379813e..ab8839c47bc7 100644
--- a/arch/x86/kvm/trace.h
+++ b/arch/x86/kvm/trace.h
@@ -1606,42 +1606,46 @@ TRACE_EVENT(kvm_hv_flush_tlb_ex,
  * Tracepoints for kvm_hv_send_ipi.
  */
 TRACE_EVENT(kvm_hv_send_ipi,
-	TP_PROTO(u32 vector, u64 processor_mask),
-	TP_ARGS(vector, processor_mask),
+	TP_PROTO(u32 vector, u64 processor_mask, u8 vtl),
+	TP_ARGS(vector, processor_mask, vtl),
 
 	TP_STRUCT__entry(
 		__field(u32, vector)
 		__field(u64, processor_mask)
+		__field(u8, vtl)
 	),
 
 	TP_fast_assign(
 		__entry->vector = vector;
 		__entry->processor_mask = processor_mask;
+		__entry->vtl = vtl;
 	),
 
-	TP_printk("vector %x processor_mask 0x%llx",
-		  __entry->vector, __entry->processor_mask)
+	TP_printk("vector %x processor_mask 0x%llx vtl %d",
+		  __entry->vector, __entry->processor_mask, __entry->vtl)
 );
 
 TRACE_EVENT(kvm_hv_send_ipi_ex,
-	TP_PROTO(u32 vector, u64 format, u64 valid_bank_mask),
-	TP_ARGS(vector, format, valid_bank_mask),
+	TP_PROTO(u32 vector, u64 format, u64 valid_bank_mask, u8 vtl),
+	TP_ARGS(vector, format, valid_bank_mask, vtl),
 
 	TP_STRUCT__entry(
 		__field(u32, vector)
 		__field(u64, format)
 		__field(u64, valid_bank_mask)
+		__field(u8, vtl)
 	),
 
 	TP_fast_assign(
 		__entry->vector = vector;
 		__entry->format = format;
 		__entry->valid_bank_mask = valid_bank_mask;
+		__entry->vtl = vtl;
 	),
 
-	TP_printk("vector %x format %llx valid_bank_mask 0x%llx",
+	TP_printk("vector %x format %llx valid_bank_mask 0x%llx vtl %d",
 		  __entry->vector, __entry->format,
-		  __entry->valid_bank_mask)
+		  __entry->valid_bank_mask, __entry->vtl)
 );
 
 TRACE_EVENT(kvm_pv_tlb_flush,
diff --git a/include/asm-generic/hyperv-tlfs.h b/include/asm-generic/hyperv-tlfs.h
index 0e7643c1ef01..40d7dc793c03 100644
--- a/include/asm-generic/hyperv-tlfs.h
+++ b/include/asm-generic/hyperv-tlfs.h
@@ -424,14 +424,16 @@ struct hv_vpset {
 /* HvCallSendSyntheticClusterIpi hypercall */
 struct hv_send_ipi {
 	u32 vector;
-	u32 reserved;
+	union hv_input_vtl in_vtl;
+	u8 reserved[3];
 	u64 cpu_mask;
 } __packed;
 
 /* HvCallSendSyntheticClusterIpiEx hypercall */
 struct hv_send_ipi_ex {
 	u32 vector;
-	u32 reserved;
+	union hv_input_vtl in_vtl;
+	u8 reserved[3];
 	struct hv_vpset vp_set;
 } __packed;
 
-- 
2.40.1