x86: allow disabling the emulated PIC

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>

diff --git a/xen/arch/x86/hvm/vpic.c b/xen/arch/x86/hvm/vpic.c
index 7c2edc888b12b8a5d354c5fa8adf770fcc90955e..6a2e87b32ae8ba4fa6e5cdc336c7dba4bc39ff0f 100644 (file)
--- a/xen/arch/x86/hvm/vpic.c
+++ b/xen/arch/x86/hvm/vpic.c
@@ -377,6 +377,9 @@ static int vpic_save(struct domain *d, hvm_domain_context_t *h)
     struct hvm_hw_vpic *s;
     int i;
 
+    if ( !has_vpic(d) )
+        return 0;
+
     /* Save the state of both PICs */
     for ( i = 0; i < 2 ; i++ )
     {
@@ -392,7 +395,10 @@ static int vpic_load(struct domain *d, hvm_domain_context_t *h)
 {
     struct hvm_hw_vpic *s;
     uint16_t inst;
-    
+
+    if ( !has_vpic(d) )
+        return -ENODEV;
+
     /* Which PIC is this? */
     inst = hvm_load_instance(h);
     if ( inst > 1 )
@@ -412,6 +418,9 @@ void vpic_reset(struct domain *d)
 {
     struct hvm_hw_vpic *vpic;
 
+    if ( !has_vpic(d) )
+        return;
+
     /* Master PIC. */
     vpic = &d->arch.hvm_domain.vpic[0];
     memset(vpic, 0, sizeof(*vpic));
@@ -425,6 +434,9 @@ void vpic_reset(struct domain *d)
 
 void vpic_init(struct domain *d)
 {
+    if ( !has_vpic(d) )
+        return;
+
     vpic_reset(d);
 
     register_portio_handler(d, 0x20, 2, vpic_intercept_pic_io);
@@ -439,6 +451,7 @@ void vpic_irq_positive_edge(struct domain *d, int irq)
     struct hvm_hw_vpic *vpic = &d->arch.hvm_domain.vpic[irq >> 3];
     uint8_t mask = 1 << (irq & 7);
 
+    ASSERT(has_vpic(d));
     ASSERT(irq <= 15);
     ASSERT(vpic_is_locked(vpic));
 
@@ -456,6 +469,7 @@ void vpic_irq_negative_edge(struct domain *d, int irq)
     struct hvm_hw_vpic *vpic = &d->arch.hvm_domain.vpic[irq >> 3];
     uint8_t mask = 1 << (irq & 7);
 
+    ASSERT(has_vpic(d));
     ASSERT(irq <= 15);
     ASSERT(vpic_is_locked(vpic));
 
@@ -473,6 +487,8 @@ int vpic_ack_pending_irq(struct vcpu *v)
     int irq, vector;
     struct hvm_hw_vpic *vpic = &v->domain->arch.hvm_domain.vpic[0];
 
+    ASSERT(has_vpic(v->domain));
+
     TRACE_2D(TRC_HVM_EMUL_PIC_PEND_IRQ_CALL, vlapic_accept_pic_intr(v),
              vpic->int_output);
     if ( !vlapic_accept_pic_intr(v) || !vpic->int_output )