x86/HVM: EOI handling function adjustments

The vector parameters are more usefully u8 right away. This is
particularly important for the vioapic_update_EOI() invocation from
vioapic_write() (which luckily is only a latent issue, as
VIOAPIC_VERSION_ID is still hard coded to 0x11 right now). But it at
once allows simplifying VMX's EXIT_REASON_EOI_INDUCED handling (the
kind of pointless helper function should have been static anyway; not
being use for anything else, it gets removed altogether).

Plus vlapic_handle_EOI() (now renamed for that purpose) can be used as
the tail of vlapic_EOI_set() instead of duplicating that code.

Finally replace a stray current->domain use in vlapic_handle_EOI().

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>

xen/arch/x86/hvm/vioapic.c

@@ -386,7 +386,7 @@ void vioapic_irq_positive_edge(struct domain *d, unsigned int irq)
     }
 }
 
-void vioapic_update_EOI(struct domain *d, int vector)
+void vioapic_update_EOI(struct domain *d, u8 vector)
 {
     struct hvm_hw_vioapic *vioapic = domain_vioapic(d);
     struct hvm_irq *hvm_irq = &d->arch.hvm_domain.irq;

xen/arch/x86/hvm/vlapic.c

@@ -421,18 +421,17 @@ void vlapic_EOI_set(struct vlapic *vlapic)
     if ( hvm_funcs.handle_eoi )
         hvm_funcs.handle_eoi(vector);
 
-    if ( vlapic_test_and_clear_vector(vector, &vlapic->regs->data[APIC_TMR]) )
-        vioapic_update_EOI(vlapic_domain(vlapic), vector);
-
-    hvm_dpci_msi_eoi(current->domain, vector);
+    vlapic_handle_EOI(vlapic, vector);
 }
 
-void vlapic_handle_EOI_induced_exit(struct vlapic *vlapic, int vector)
+void vlapic_handle_EOI(struct vlapic *vlapic, u8 vector)
 {
-    if ( vlapic_test_and_clear_vector(vector, &vlapic->regs->data[APIC_TMR]) )
-        vioapic_update_EOI(vlapic_domain(vlapic), vector);
+    struct domain *d = vlapic_domain(vlapic);
 
-    hvm_dpci_msi_eoi(current->domain, vector);
+    if ( vlapic_test_and_clear_vector(vector, &vlapic->regs->data[APIC_TMR]) )
+        vioapic_update_EOI(d, vector);
+
+    hvm_dpci_msi_eoi(d, vector);
 }
 
 static bool_t is_multicast_dest(struct vlapic *vlapic, unsigned int short_hand,

xen/arch/x86/hvm/vmx/vmx.c

@@ -2683,17 +2683,6 @@ static int vmx_handle_apic_write(void)
     return vlapic_apicv_write(current, exit_qualification & 0xfff);
 }
 
-/*
- * When "Virtual Interrupt Delivery" is enabled, this function is used
- * to handle EOI-induced VM exit
- */
-void vmx_handle_EOI_induced_exit(struct vlapic *vlapic, int vector)
-{
-    ASSERT(cpu_has_vmx_virtual_intr_delivery);
-
-    vlapic_handle_EOI_induced_exit(vlapic, vector);
-}
-
 void vmx_vmexit_handler(struct cpu_user_regs *regs)
 {
     unsigned long exit_qualification, exit_reason, idtv_info, intr_info = 0;
@@ -3127,15 +3116,12 @@ void vmx_vmexit_handler(struct cpu_user_regs *regs)
         break;
 
     case EXIT_REASON_EOI_INDUCED:
-    {
-        int vector;
-
         __vmread(EXIT_QUALIFICATION, &exit_qualification);
-        vector = exit_qualification & 0xff;
 
-        vmx_handle_EOI_induced_exit(vcpu_vlapic(v), vector);
+        ASSERT(cpu_has_vmx_virtual_intr_delivery);
+
+        vlapic_handle_EOI(vcpu_vlapic(v), exit_qualification);
         break;
-    }
 
     case EXIT_REASON_IO_INSTRUCTION:
         __vmread(EXIT_QUALIFICATION, &exit_qualification);

xen/include/asm-x86/hvm/vioapic.h

@@ -62,6 +62,6 @@ int vioapic_init(struct domain *d);
 void vioapic_deinit(struct domain *d);
 void vioapic_reset(struct domain *d);
 void vioapic_irq_positive_edge(struct domain *d, unsigned int irq);
-void vioapic_update_EOI(struct domain *d, int vector);
+void vioapic_update_EOI(struct domain *d, u8 vector);
 
 #endif /* __ASM_X86_HVM_VIOAPIC_H__ */

xen/include/asm-x86/hvm/vlapic.h

@@ -127,7 +127,7 @@ uint32_t vlapic_set_ppr(struct vlapic *vlapic);
 void vlapic_adjust_i8259_target(struct domain *d);
 
 void vlapic_EOI_set(struct vlapic *vlapic);
-void vlapic_handle_EOI_induced_exit(struct vlapic *vlapic, int vector);
+void vlapic_handle_EOI(struct vlapic *vlapic, u8 vector);
 
 void vlapic_ipi(struct vlapic *vlapic, uint32_t icr_low, uint32_t icr_high);