diff --git a/arch/x86/include/asm/irq_vectors.h b/arch/x86/include/asm/irq_vectors.h
index 8767d99c4f64d9a7fc70a17d338ffe4770a5e969..e2ca3009255706910d1ddc407232f4d09f011f24 100644
--- a/arch/x86/include/asm/irq_vectors.h
+++ b/arch/x86/include/asm/irq_vectors.h
@@ -125,6 +125,9 @@
*/
#define MCE_SELF_VECTOR 0xeb
+/* Xen vector callback to receive events in a HVM domain */
+#define XEN_HVM_EVTCHN_CALLBACK 0xe9
+
#define NR_VECTORS 256
#define FPU_IRQ 13
diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S
index cd49141cf153fb124dc46a6497dbc863a3c81ad9..6b196834a0dd909c5988267ca516b793c6691316 100644
--- a/arch/x86/kernel/entry_32.S
+++ b/arch/x86/kernel/entry_32.S
@@ -1166,6 +1166,9 @@ ENTRY(xen_failsafe_callback)
.previous
ENDPROC(xen_failsafe_callback)
+BUILD_INTERRUPT3(xen_hvm_callback_vector, XEN_HVM_EVTCHN_CALLBACK,
+ xen_evtchn_do_upcall)
+
#endif /* CONFIG_XEN */
#ifdef CONFIG_FUNCTION_TRACER
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index 0697ff139837644f170f032ae525d9e112c71681..490ae2bb18a854d568496dd054bd6ec715ce02bf 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -1329,6 +1329,9 @@ ENTRY(xen_failsafe_callback)
CFI_ENDPROC
END(xen_failsafe_callback)
+apicinterrupt XEN_HVM_EVTCHN_CALLBACK \
+ xen_hvm_callback_vector xen_evtchn_do_upcall
+
#endif /* CONFIG_XEN */
/*
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 09b36e9d507a27faef564956802a55141558bae8..b211a04c4b2ccbb6f1ad2c4b2388592532dff2f0 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -11,6 +11,7 @@
* Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
*/
+#include <linux/cpu.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/smp.h>
@@ -38,6 +39,7 @@
#include <xen/interface/memory.h>
#include <xen/features.h>
#include <xen/page.h>
+#include <xen/hvm.h>
#include <xen/hvc-console.h>
#include <asm/paravirt.h>
@@ -80,6 +82,8 @@ struct shared_info xen_dummy_shared_info;
void *xen_initial_gdt;
RESERVE_BRK(shared_info_page_brk, PAGE_SIZE);
+__read_mostly int xen_have_vector_callback;
+EXPORT_SYMBOL_GPL(xen_have_vector_callback);
/*
* Point at some empty memory to start with. We map the real shared_info
@@ -1277,6 +1281,24 @@ static void __init init_shared_info(void)
per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0];
}
+static int __cpuinit xen_hvm_cpu_notify(struct notifier_block *self,
+ unsigned long action, void *hcpu)
+{
+ int cpu = (long)hcpu;
+ switch (action) {
+ case CPU_UP_PREPARE:
+ per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
+ break;
+ default:
+ break;
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block __cpuinitdata xen_hvm_cpu_notifier = {
+ .notifier_call = xen_hvm_cpu_notify,
+};
+
static void __init xen_hvm_guest_init(void)
{
int r;
@@ -1287,6 +1309,12 @@ static void __init xen_hvm_guest_init(void)
return;
init_shared_info();
+
+ if (xen_feature(XENFEAT_hvm_callback_vector))
+ xen_have_vector_callback = 1;
+ register_cpu_notifier(&xen_hvm_cpu_notifier);
+ have_vcpu_info_placement = 0;
+ x86_init.irqs.intr_init = xen_init_IRQ;
}
static bool __init xen_hvm_platform(void)
diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h
index f9153a300bcee998e1f78f95a202cc9036df79ca..0d0e0e6a747991f9904d78dc3b3fb91ec26992b1 100644
--- a/arch/x86/xen/xen-ops.h
+++ b/arch/x86/xen/xen-ops.h
@@ -38,6 +38,8 @@ void xen_enable_sysenter(void);
void xen_enable_syscall(void);
void xen_vcpu_restore(void);
+void xen_callback_vector(void);
+
void __init xen_build_dynamic_phys_to_machine(void);
void xen_init_irq_ops(void);
diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index db8f506817f0ad30f2b54bde0ff778a7405ba59b..d659480125f07885164353c75b83a1174049b897 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -29,6 +29,7 @@
#include <linux/bootmem.h>
#include <linux/slab.h>
+#include <asm/desc.h>
#include <asm/ptrace.h>
#include <asm/irq.h>
#include <asm/idle.h>
@@ -36,10 +37,14 @@
#include <asm/xen/hypercall.h>
#include <asm/xen/hypervisor.h>
+#include <xen/xen.h>
+#include <xen/hvm.h>
#include <xen/xen-ops.h>
#include <xen/events.h>
#include <xen/interface/xen.h>
#include <xen/interface/event_channel.h>
+#include <xen/interface/hvm/hvm_op.h>
+#include <xen/interface/hvm/params.h>
/*
* This lock protects updates to the following mapping and reference-count
@@ -617,17 +622,13 @@ static DEFINE_PER_CPU(unsigned, xed_nesting_count);
* a bitset of words which contain pending event bits. The second
* level is a bitset of pending events themselves.
*/
-void xen_evtchn_do_upcall(struct pt_regs *regs)
+static void __xen_evtchn_do_upcall(void)
{
int cpu = get_cpu();
- struct pt_regs *old_regs = set_irq_regs(regs);
struct shared_info *s = HYPERVISOR_shared_info;
struct vcpu_info *vcpu_info = __get_cpu_var(xen_vcpu);
unsigned count;
- exit_idle();
- irq_enter();
-
do {
unsigned long pending_words;
@@ -667,10 +668,26 @@ void xen_evtchn_do_upcall(struct pt_regs *regs)
} while(count != 1);
out:
+
+ put_cpu();
+}
+
+void xen_evtchn_do_upcall(struct pt_regs *regs)
+{
+ struct pt_regs *old_regs = set_irq_regs(regs);
+
+ exit_idle();
+ irq_enter();
+
+ __xen_evtchn_do_upcall();
+
irq_exit();
set_irq_regs(old_regs);
+}
- put_cpu();
+void xen_hvm_evtchn_do_upcall(void)
+{
+ __xen_evtchn_do_upcall();
}
/* Rebind a new event channel to an existing irq. */
@@ -933,6 +950,40 @@ static struct irq_chip xen_dynamic_chip __read_mostly = {
.retrigger = retrigger_dynirq,
};
+int xen_set_callback_via(uint64_t via)
+{
+ struct xen_hvm_param a;
+ a.domid = DOMID_SELF;
+ a.index = HVM_PARAM_CALLBACK_IRQ;
+ a.value = via;
+ return HYPERVISOR_hvm_op(HVMOP_set_param, &a);
+}
+EXPORT_SYMBOL_GPL(xen_set_callback_via);
+
+/* Vector callbacks are better than PCI interrupts to receive event
+ * channel notifications because we can receive vector callbacks on any
+ * vcpu and we don't need PCI support or APIC interactions. */
+void xen_callback_vector(void)
+{
+ int rc;
+ uint64_t callback_via;
+ if (xen_have_vector_callback) {
+ callback_via = HVM_CALLBACK_VECTOR(XEN_HVM_EVTCHN_CALLBACK);
+ rc = xen_set_callback_via(callback_via);
+ if (rc) {
+ printk(KERN_ERR "Request for Xen HVM callback vector"
+ " failed.\n");
+ xen_have_vector_callback = 0;
+ return;
+ }
+ printk(KERN_INFO "Xen HVM callback vector for event delivery is "
+ "enabled\n");
+ /* in the restore case the vector has already been allocated */
+ if (!test_bit(XEN_HVM_EVTCHN_CALLBACK, used_vectors))
+ alloc_intr_gate(XEN_HVM_EVTCHN_CALLBACK, xen_hvm_callback_vector);
+ }
+}
+
void __init xen_init_IRQ(void)
{
int i;
@@ -947,5 +998,10 @@ void __init xen_init_IRQ(void)
for (i = 0; i < NR_EVENT_CHANNELS; i++)
mask_evtchn(i);
- irq_ctx_init(smp_processor_id());
+ if (xen_hvm_domain()) {
+ xen_callback_vector();
+ native_init_IRQ();
+ } else {
+ irq_ctx_init(smp_processor_id());
+ }
}
diff --git a/include/xen/events.h b/include/xen/events.h
index e68d59a90ca88b73c21b431c3cf538165916d5a7..a15d93262e308706eb4f3fe6a1283d0583f2b043 100644
--- a/include/xen/events.h
+++ b/include/xen/events.h
@@ -56,4 +56,11 @@ void xen_poll_irq(int irq);
/* Determine the IRQ which is bound to an event channel */
unsigned irq_from_evtchn(unsigned int evtchn);
+/* Xen HVM evtchn vector callback */
+extern void xen_hvm_callback_vector(void);
+extern int xen_have_vector_callback;
+int xen_set_callback_via(uint64_t via);
+void xen_evtchn_do_upcall(struct pt_regs *regs);
+void xen_hvm_evtchn_do_upcall(void);
+
#endif /* _XEN_EVENTS_H */
diff --git a/include/xen/hvm.h b/include/xen/hvm.h
index 5dfe8fb86e6735df3b75370f8715ac321d2cafac..b193fa2f9fddb2ef6670a7e1aa7f27ef4b60edbe 100644
--- a/include/xen/hvm.h
+++ b/include/xen/hvm.h
@@ -3,6 +3,7 @@
#define XEN_HVM_H__
#include <xen/interface/hvm/params.h>
+#include <asm/xen/hypercall.h>
static inline int hvm_get_parameter(int idx, uint64_t *value)
{
@@ -21,4 +22,9 @@ static inline int hvm_get_parameter(int idx, uint64_t *value)
return r;
}
+#define HVM_CALLBACK_VIA_TYPE_VECTOR 0x2
+#define HVM_CALLBACK_VIA_TYPE_SHIFT 56
+#define HVM_CALLBACK_VECTOR(x) (((uint64_t)HVM_CALLBACK_VIA_TYPE_VECTOR)<<\
+ HVM_CALLBACK_VIA_TYPE_SHIFT | (x))
+
#endif /* XEN_HVM_H__ */
diff --git a/include/xen/interface/features.h b/include/xen/interface/features.h
index f51b6413b05469abab7724717b465f7277137612..8ab08b91bf6f99f8580be7f15ba23dc6006c1c55 100644
--- a/include/xen/interface/features.h
+++ b/include/xen/interface/features.h
@@ -41,6 +41,9 @@
/* x86: Does this Xen host support the MMU_PT_UPDATE_PRESERVE_AD hypercall? */
#define XENFEAT_mmu_pt_update_preserve_ad 5
+/* x86: Does this Xen host support the HVM callback vector type? */
+#define XENFEAT_hvm_callback_vector 8
+
#define XENFEAT_NR_SUBMAPS 1
#endif /* __XEN_PUBLIC_FEATURES_H__ */