[PATCH 02/13] KVM: Initialize VT-d Posted-Interrtups Descriptor

[Feng Wu <feng.wu@intel.com>]

This patch initialize the VT-d Posted-interrupt Descritpor.

Signed-off-by: Feng Wu <feng.wu@intel.com>
---
 arch/x86/include/asm/irq_remapping.h |    1 +
 arch/x86/kernel/apic/apic.c          |    1 +
 arch/x86/kvm/vmx.c                   |   56 ++++++++++++++++++++++++++++++++-
 3 files changed, 56 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/irq_remapping.h b/arch/x86/include/asm/irq_remapping.h
index b7747c4..a3cc437 100644
--- a/arch/x86/include/asm/irq_remapping.h
+++ b/arch/x86/include/asm/irq_remapping.h
@@ -57,6 +57,7 @@ extern bool setup_remapped_irq(int irq,
 			       struct irq_chip *chip);
 
 void irq_remap_modify_chip_defaults(struct irq_chip *chip);
+extern int irq_post_enabled;
 
 #else  /* CONFIG_IRQ_REMAP */
 
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index ba6cc04..987408d 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -162,6 +162,7 @@ __setup("apicpmtimer", setup_apicpmtimer);
 #endif
 
 int x2apic_mode;
+EXPORT_SYMBOL_GPL(x2apic_mode);
 #ifdef CONFIG_X86_X2APIC
 /* x2apic enabled before OS handover */
 int x2apic_preenabled;
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 3e556c6..a4670d3 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -45,6 +45,7 @@
 #include <asm/perf_event.h>
 #include <asm/debugreg.h>
 #include <asm/kexec.h>
+#include <asm/irq_remapping.h>
 
 #include "trace.h"
 
@@ -408,13 +409,32 @@ struct nested_vmx {
 };
 
 #define POSTED_INTR_ON  0
+#define POSTED_INTR_SN  1
+
 /* Posted-Interrupt Descriptor */
 struct pi_desc {
 	u32 pir[8];     /* Posted interrupt requested */
-	u32 control;	/* bit 0 of control is outstanding notification bit */
-	u32 rsvd[7];
+	union {
+		struct {
+			u64	on	: 1,
+				sn	: 1,
+				rsvd_1	: 13,
+				ndm	: 1,
+				nv	: 8,
+				rsvd_2	: 8,
+				ndst	: 32;
+		};
+		u64 control;
+	};
+	u32 rsvd[6];
 } __aligned(64);
 
+static void pi_clear_sn(struct pi_desc *pi_desc)
+{
+	return clear_bit(POSTED_INTR_SN,
+			(unsigned long *)&pi_desc->control);
+}
+
 static bool pi_test_and_set_on(struct pi_desc *pi_desc)
 {
 	return test_and_set_bit(POSTED_INTR_ON,
@@ -4396,6 +4416,33 @@ static void ept_set_mmio_spte_mask(void)
 	kvm_mmu_set_mmio_spte_mask((0x3ull << 62) | 0x6ull);
 }
 
+static bool pi_desc_init(struct vcpu_vmx *vmx)
+{
+	unsigned int dest;
+
+	if (irq_post_enabled == 0)
+		return true;
+
+	/*
+	 * Initialize Posted-Interrupt Descriptor
+	 */
+
+	pi_clear_sn(&vmx->pi_desc);
+	vmx->pi_desc.nv = POSTED_INTR_VECTOR;
+
+	/* Physical mode for Notificaiton Event */
+	vmx->pi_desc.ndm = 0;
+	dest = cpu_physical_id(vmx->vcpu.cpu);
+
+	if (x2apic_mode)
+		vmx->pi_desc.ndst = dest;
+	else
+		vmx->pi_desc.ndst = (dest << 8) & 0xFF00;
+
+	return true;
+}
+
+
 /*
  * Sets up the vmcs for emulated real mode.
  */
@@ -4439,6 +4486,11 @@ static int vmx_vcpu_setup(struct vcpu_vmx *vmx)
 
 		vmcs_write64(POSTED_INTR_NV, POSTED_INTR_VECTOR);
 		vmcs_write64(POSTED_INTR_DESC_ADDR, __pa((&vmx->pi_desc)));
+
+		if (!pi_desc_init(vmx)) {
+			printk(KERN_ERR "Initialize PI descriptor error!\n");
+			return 1;
+		}
 	}
 
 	if (ple_gap) {
-- 
1.7.1