kvm: x86: Extended struct kvm_lapic_irq with msi_redir_hint for MSI delivery

Extended struct kvm_lapic_irq with bool msi_redir_hint, which will
be used to determine if the delivery of the MSI should target only
the lowest priority CPU in the logical group specified for delivery.
(In physical dest mode, the RH bit is not relevant). Initialized the value
of msi_redir_hint to true when RH=1 in kvm_set_msi_irq(), and initialized
to false in all other cases.

Added value of msi_redir_hint to a debug message dump of an IRQ in
apic_send_ipi().

Signed-off-by: James Sullivan <sullivan.james.f@gmail.com>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

4 files changed, 8 insertions, 3 deletions

diff --git a/arch/x86/kvm/ioapic.c b/arch/x86/kvm/ioapic.c
index 28146f03c514..274663496f7a 100644
--- a/arch/x86/kvm/ioapic.c
+++ b/arch/x86/kvm/ioapic.c
@@ -349,6 +349,7 @@ static int ioapic_service(struct kvm_ioapic *ioapic, int irq, bool line_status)
 	irqe.delivery_mode = entry->fields.delivery_mode << 8;
 	irqe.level = 1;
 	irqe.shorthand = 0;
+	irqe.msi_redir_hint = false;
 
 	if (irqe.trig_mode == IOAPIC_EDGE_TRIG)
 		ioapic->irr_delivered |= 1 << irq;
diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
index 72298b3ac025..80c10af2bf46 100644
--- a/arch/x86/kvm/irq_comm.c
+++ b/arch/x86/kvm/irq_comm.c
@@ -106,9 +106,10 @@ static inline void kvm_set_msi_irq(struct kvm_kernel_irq_routing_entry *e,
 	irq->dest_mode = (1 << MSI_ADDR_DEST_MODE_SHIFT) & e->msi.address_lo;
 	irq->trig_mode = (1 << MSI_DATA_TRIGGER_SHIFT) & e->msi.data;
 	irq->delivery_mode = e->msi.data & 0x700;
+	irq->msi_redir_hint = ((e->msi.address_lo
+		& MSI_ADDR_REDIRECTION_LOWPRI) > 0);
 	irq->level = 1;
 	irq->shorthand = 0;
-	/* TODO Deal with RH bit of MSI message address */
 }
 
 int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index ba585d0c42c5..2573b29bbbb3 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -917,6 +917,7 @@ static void apic_send_ipi(struct kvm_lapic *apic)
 	irq.level = (icr_low & APIC_INT_ASSERT) != 0;
 	irq.trig_mode = icr_low & APIC_INT_LEVELTRIG;
 	irq.shorthand = icr_low & APIC_SHORT_MASK;
+	irq.msi_redir_hint = false;
 	if (apic_x2apic_mode(apic))
 		irq.dest_id = icr_high;
 	else
@@ -926,10 +927,11 @@ static void apic_send_ipi(struct kvm_lapic *apic)
 
 	apic_debug("icr_high 0x%x, icr_low 0x%x, "
 		   "short_hand 0x%x, dest 0x%x, trig_mode 0x%x, level 0x%x, "
-		   "dest_mode 0x%x, delivery_mode 0x%x, vector 0x%x\n",
+		   "dest_mode 0x%x, delivery_mode 0x%x, vector 0x%x, "
+		   "msi_redir_hint 0x%x\n",
 		   icr_high, icr_low, irq.shorthand, irq.dest_id,
 		   irq.trig_mode, irq.level, irq.dest_mode, irq.delivery_mode,
-		   irq.vector);
+		   irq.vector, irq.msi_redir_hint);
 
 	kvm_irq_delivery_to_apic(apic->vcpu->kvm, apic, &irq, NULL);
 }
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 755a79fabfc1..bf80ce7656b7 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5984,6 +5984,7 @@ static void kvm_pv_kick_cpu_op(struct kvm *kvm, unsigned long flags, int apicid)
 	lapic_irq.shorthand = 0;
 	lapic_irq.dest_mode = 0;
 	lapic_irq.dest_id = apicid;
+	lapic_irq.msi_redir_hint = false;
 
 	lapic_irq.delivery_mode = APIC_DM_REMRD;
 	kvm_irq_delivery_to_apic(kvm, NULL, &lapic_irq, NULL);