events.c 35.1 KB
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/*
 * Xen event channels
 *
 * Xen models interrupts with abstract event channels.  Because each
 * domain gets 1024 event channels, but NR_IRQ is not that large, we
 * must dynamically map irqs<->event channels.  The event channels
 * interface with the rest of the kernel by defining a xen interrupt
 * chip.  When an event is recieved, it is mapped to an irq and sent
 * through the normal interrupt processing path.
 *
 * There are four kinds of events which can be mapped to an event
 * channel:
 *
 * 1. Inter-domain notifications.  This includes all the virtual
 *    device events, since they're driven by front-ends in another domain
 *    (typically dom0).
 * 2. VIRQs, typically used for timers.  These are per-cpu events.
 * 3. IPIs.
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 * 4. PIRQs - Hardware interrupts.
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 *
 * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
 */

#include <linux/linkage.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/string.h>
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#include <linux/bootmem.h>
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#include <linux/slab.h>
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#include <linux/irqnr.h>
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#include <linux/pci.h>
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#include <asm/desc.h>
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#include <asm/ptrace.h>
#include <asm/irq.h>
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#include <asm/idle.h>
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#include <asm/io_apic.h>
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#include <asm/sync_bitops.h>
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#include <asm/xen/pci.h>
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#include <asm/xen/hypercall.h>
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#include <asm/xen/hypervisor.h>
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#include <xen/xen.h>
#include <xen/hvm.h>
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#include <xen/xen-ops.h>
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#include <xen/events.h>
#include <xen/interface/xen.h>
#include <xen/interface/event_channel.h>
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#include <xen/interface/hvm/hvm_op.h>
#include <xen/interface/hvm/params.h>
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/*
 * This lock protects updates to the following mapping and reference-count
 * arrays. The lock does not need to be acquired to read the mapping tables.
 */
static DEFINE_SPINLOCK(irq_mapping_update_lock);

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static LIST_HEAD(xen_irq_list_head);

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/* IRQ <-> VIRQ mapping. */
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static DEFINE_PER_CPU(int [NR_VIRQS], virq_to_irq) = {[0 ... NR_VIRQS-1] = -1};
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/* IRQ <-> IPI mapping */
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static DEFINE_PER_CPU(int [XEN_NR_IPIS], ipi_to_irq) = {[0 ... XEN_NR_IPIS-1] = -1};
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/* Interrupt types. */
enum xen_irq_type {
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	IRQT_UNBOUND = 0,
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	IRQT_PIRQ,
	IRQT_VIRQ,
	IRQT_IPI,
	IRQT_EVTCHN
};
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/*
 * Packed IRQ information:
 * type - enum xen_irq_type
 * event channel - irq->event channel mapping
 * cpu - cpu this event channel is bound to
 * index - type-specific information:
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 *    PIRQ - vector, with MSB being "needs EIO", or physical IRQ of the HVM
 *           guest, or GSI (real passthrough IRQ) of the device.
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 *    VIRQ - virq number
 *    IPI - IPI vector
 *    EVTCHN -
 */
struct irq_info
{
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	struct list_head list;
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	enum xen_irq_type type;	/* type */
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	unsigned irq;
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	unsigned short evtchn;	/* event channel */
	unsigned short cpu;	/* cpu bound */

	union {
		unsigned short virq;
		enum ipi_vector ipi;
		struct {
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			unsigned short pirq;
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			unsigned short gsi;
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			unsigned char vector;
			unsigned char flags;
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		} pirq;
	} u;
};
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#define PIRQ_NEEDS_EOI	(1 << 0)
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#define PIRQ_SHAREABLE	(1 << 1)
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static struct irq_info *irq_info;
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static int *pirq_to_irq;
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static int *evtchn_to_irq;
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static DEFINE_PER_CPU(unsigned long [NR_EVENT_CHANNELS/BITS_PER_LONG],
		      cpu_evtchn_mask);
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/* Xen will never allocate port zero for any purpose. */
#define VALID_EVTCHN(chn)	((chn) != 0)

static struct irq_chip xen_dynamic_chip;
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static struct irq_chip xen_percpu_chip;
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static struct irq_chip xen_pirq_chip;
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/* Get info for IRQ */
static struct irq_info *info_for_irq(unsigned irq)
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{
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	return &irq_info[irq];
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}

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/* Constructors for packed IRQ information. */
static void xen_irq_info_common_init(struct irq_info *info,
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				     unsigned irq,
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				     enum xen_irq_type type,
				     unsigned short evtchn,
				     unsigned short cpu)
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{
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	BUG_ON(info->type != IRQT_UNBOUND && info->type != type);

	info->type = type;
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	info->irq = irq;
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	info->evtchn = evtchn;
	info->cpu = cpu;
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	evtchn_to_irq[evtchn] = irq;
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}

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static void xen_irq_info_evtchn_init(unsigned irq,
				     unsigned short evtchn)
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{
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	struct irq_info *info = info_for_irq(irq);

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	xen_irq_info_common_init(info, irq, IRQT_EVTCHN, evtchn, 0);
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}

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static void xen_irq_info_ipi_init(unsigned cpu,
				  unsigned irq,
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				  unsigned short evtchn,
				  enum ipi_vector ipi)
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{
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	struct irq_info *info = info_for_irq(irq);

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	xen_irq_info_common_init(info, irq, IRQT_IPI, evtchn, 0);
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	info->u.ipi = ipi;
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	per_cpu(ipi_to_irq, cpu)[ipi] = irq;
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}

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static void xen_irq_info_virq_init(unsigned cpu,
				   unsigned irq,
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				   unsigned short evtchn,
				   unsigned short virq)
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{
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	struct irq_info *info = info_for_irq(irq);

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	xen_irq_info_common_init(info, irq, IRQT_VIRQ, evtchn, 0);
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	info->u.virq = virq;
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	per_cpu(virq_to_irq, cpu)[virq] = irq;
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}

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static void xen_irq_info_pirq_init(unsigned irq,
				   unsigned short evtchn,
				   unsigned short pirq,
				   unsigned short gsi,
				   unsigned short vector,
				   unsigned char flags)
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{
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	struct irq_info *info = info_for_irq(irq);

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	xen_irq_info_common_init(info, irq, IRQT_PIRQ, evtchn, 0);
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	info->u.pirq.pirq = pirq;
	info->u.pirq.gsi = gsi;
	info->u.pirq.vector = vector;
	info->u.pirq.flags = flags;
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	pirq_to_irq[pirq] = irq;
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}

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/*
 * Accessors for packed IRQ information.
 */
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static unsigned int evtchn_from_irq(unsigned irq)
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{
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	if (unlikely(WARN(irq < 0 || irq >= nr_irqs, "Invalid irq %d!\n", irq)))
		return 0;

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	return info_for_irq(irq)->evtchn;
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}

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unsigned irq_from_evtchn(unsigned int evtchn)
{
	return evtchn_to_irq[evtchn];
}
EXPORT_SYMBOL_GPL(irq_from_evtchn);

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static enum ipi_vector ipi_from_irq(unsigned irq)
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{
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	struct irq_info *info = info_for_irq(irq);

	BUG_ON(info == NULL);
	BUG_ON(info->type != IRQT_IPI);

	return info->u.ipi;
}

static unsigned virq_from_irq(unsigned irq)
{
	struct irq_info *info = info_for_irq(irq);

	BUG_ON(info == NULL);
	BUG_ON(info->type != IRQT_VIRQ);

	return info->u.virq;
}

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static unsigned pirq_from_irq(unsigned irq)
{
	struct irq_info *info = info_for_irq(irq);

	BUG_ON(info == NULL);
	BUG_ON(info->type != IRQT_PIRQ);

	return info->u.pirq.pirq;
}

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static unsigned gsi_from_irq(unsigned irq)
{
	struct irq_info *info = info_for_irq(irq);

	BUG_ON(info == NULL);
	BUG_ON(info->type != IRQT_PIRQ);

	return info->u.pirq.gsi;
}

static enum xen_irq_type type_from_irq(unsigned irq)
{
	return info_for_irq(irq)->type;
}

static unsigned cpu_from_irq(unsigned irq)
{
	return info_for_irq(irq)->cpu;
}

static unsigned int cpu_from_evtchn(unsigned int evtchn)
{
	int irq = evtchn_to_irq[evtchn];
	unsigned ret = 0;

	if (irq != -1)
		ret = cpu_from_irq(irq);

	return ret;
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}

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static bool pirq_needs_eoi(unsigned irq)
{
	struct irq_info *info = info_for_irq(irq);

	BUG_ON(info->type != IRQT_PIRQ);

	return info->u.pirq.flags & PIRQ_NEEDS_EOI;
}

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static inline unsigned long active_evtchns(unsigned int cpu,
					   struct shared_info *sh,
					   unsigned int idx)
{
	return (sh->evtchn_pending[idx] &
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		per_cpu(cpu_evtchn_mask, cpu)[idx] &
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		~sh->evtchn_mask[idx]);
}

static void bind_evtchn_to_cpu(unsigned int chn, unsigned int cpu)
{
	int irq = evtchn_to_irq[chn];

	BUG_ON(irq == -1);
#ifdef CONFIG_SMP
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	cpumask_copy(irq_to_desc(irq)->irq_data.affinity, cpumask_of(cpu));
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#endif

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	clear_bit(chn, per_cpu(cpu_evtchn_mask, cpu_from_irq(irq)));
	set_bit(chn, per_cpu(cpu_evtchn_mask, cpu));
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	irq_info[irq].cpu = cpu;
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}

static void init_evtchn_cpu_bindings(void)
{
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	int i;
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#ifdef CONFIG_SMP
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	struct irq_info *info;
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	/* By default all event channels notify CPU#0. */
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	list_for_each_entry(info, &xen_irq_list_head, list) {
		struct irq_desc *desc = irq_to_desc(info->irq);
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		cpumask_copy(desc->irq_data.affinity, cpumask_of(0));
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	}
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#endif

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	for_each_possible_cpu(i)
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		memset(per_cpu(cpu_evtchn_mask, i),
		       (i == 0) ? ~0 : 0, sizeof(*per_cpu(cpu_evtchn_mask, i)));
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}

static inline void clear_evtchn(int port)
{
	struct shared_info *s = HYPERVISOR_shared_info;
	sync_clear_bit(port, &s->evtchn_pending[0]);
}

static inline void set_evtchn(int port)
{
	struct shared_info *s = HYPERVISOR_shared_info;
	sync_set_bit(port, &s->evtchn_pending[0]);
}

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static inline int test_evtchn(int port)
{
	struct shared_info *s = HYPERVISOR_shared_info;
	return sync_test_bit(port, &s->evtchn_pending[0]);
}

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/**
 * notify_remote_via_irq - send event to remote end of event channel via irq
 * @irq: irq of event channel to send event to
 *
 * Unlike notify_remote_via_evtchn(), this is safe to use across
 * save/restore. Notifications on a broken connection are silently
 * dropped.
 */
void notify_remote_via_irq(int irq)
{
	int evtchn = evtchn_from_irq(irq);

	if (VALID_EVTCHN(evtchn))
		notify_remote_via_evtchn(evtchn);
}
EXPORT_SYMBOL_GPL(notify_remote_via_irq);

static void mask_evtchn(int port)
{
	struct shared_info *s = HYPERVISOR_shared_info;
	sync_set_bit(port, &s->evtchn_mask[0]);
}

static void unmask_evtchn(int port)
{
	struct shared_info *s = HYPERVISOR_shared_info;
	unsigned int cpu = get_cpu();

	BUG_ON(!irqs_disabled());

	/* Slow path (hypercall) if this is a non-local port. */
	if (unlikely(cpu != cpu_from_evtchn(port))) {
		struct evtchn_unmask unmask = { .port = port };
		(void)HYPERVISOR_event_channel_op(EVTCHNOP_unmask, &unmask);
	} else {
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		struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu);
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		sync_clear_bit(port, &s->evtchn_mask[0]);

		/*
		 * The following is basically the equivalent of
		 * 'hw_resend_irq'. Just like a real IO-APIC we 'lose
		 * the interrupt edge' if the channel is masked.
		 */
		if (sync_test_bit(port, &s->evtchn_pending[0]) &&
		    !sync_test_and_set_bit(port / BITS_PER_LONG,
					   &vcpu_info->evtchn_pending_sel))
			vcpu_info->evtchn_upcall_pending = 1;
	}

	put_cpu();
}

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static void xen_irq_init(unsigned irq)
{
	struct irq_info *info;
	struct irq_desc *desc = irq_to_desc(irq);

	/* By default all event channels notify CPU#0. */
	cpumask_copy(desc->irq_data.affinity, cpumask_of(0));

	info = &irq_info[irq];

	info->type = IRQT_UNBOUND;

	list_add_tail(&info->list, &xen_irq_list_head);
}

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static int xen_allocate_irq_dynamic(void)
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{
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	int first = 0;
	int irq;
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#ifdef CONFIG_X86_IO_APIC
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	/*
	 * For an HVM guest or domain 0 which see "real" (emulated or
	 * actual repectively) GSIs we allocate dynamic IRQs
	 * e.g. those corresponding to event channels or MSIs
	 * etc. from the range above those "real" GSIs to avoid
	 * collisions.
	 */
	if (xen_initial_domain() || xen_hvm_domain())
		first = get_nr_irqs_gsi();
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#endif

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retry:
	irq = irq_alloc_desc_from(first, -1);
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	if (irq == -ENOMEM && first > NR_IRQS_LEGACY) {
		printk(KERN_ERR "Out of dynamic IRQ space and eating into GSI space. You should increase nr_irqs\n");
		first = max(NR_IRQS_LEGACY, first - NR_IRQS_LEGACY);
		goto retry;
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	}
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	if (irq < 0)
		panic("No available IRQ to bind to: increase nr_irqs!\n");
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	xen_irq_init(irq);

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	return irq;
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}

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static int xen_allocate_irq_gsi(unsigned gsi)
{
	int irq;

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	/*
	 * A PV guest has no concept of a GSI (since it has no ACPI
	 * nor access to/knowledge of the physical APICs). Therefore
	 * all IRQs are dynamically allocated from the entire IRQ
	 * space.
	 */
	if (xen_pv_domain() && !xen_initial_domain())
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		return xen_allocate_irq_dynamic();

	/* Legacy IRQ descriptors are already allocated by the arch. */
	if (gsi < NR_IRQS_LEGACY)
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		irq = gsi;
	else
		irq = irq_alloc_desc_at(gsi, -1);
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	if (irq < 0)
		panic("Unable to allocate to IRQ%d (%d)\n", gsi, irq);

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	xen_irq_init(irq);

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	return irq;
}

static void xen_free_irq(unsigned irq)
{
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	struct irq_info *info = &irq_info[irq];

	info->type = IRQT_UNBOUND;

	list_del(&info->list);
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	/* Legacy IRQ descriptors are managed by the arch. */
	if (irq < NR_IRQS_LEGACY)
		return;

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	irq_free_desc(irq);
}

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static void pirq_unmask_notify(int irq)
{
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	struct physdev_eoi eoi = { .irq = pirq_from_irq(irq) };
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	if (unlikely(pirq_needs_eoi(irq))) {
		int rc = HYPERVISOR_physdev_op(PHYSDEVOP_eoi, &eoi);
		WARN_ON(rc);
	}
}

static void pirq_query_unmask(int irq)
{
	struct physdev_irq_status_query irq_status;
	struct irq_info *info = info_for_irq(irq);

	BUG_ON(info->type != IRQT_PIRQ);

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	irq_status.irq = pirq_from_irq(irq);
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	if (HYPERVISOR_physdev_op(PHYSDEVOP_irq_status_query, &irq_status))
		irq_status.flags = 0;

	info->u.pirq.flags &= ~PIRQ_NEEDS_EOI;
	if (irq_status.flags & XENIRQSTAT_needs_eoi)
		info->u.pirq.flags |= PIRQ_NEEDS_EOI;
}

static bool probing_irq(int irq)
{
	struct irq_desc *desc = irq_to_desc(irq);

	return desc && desc->action == NULL;
}

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static unsigned int __startup_pirq(unsigned int irq)
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{
	struct evtchn_bind_pirq bind_pirq;
	struct irq_info *info = info_for_irq(irq);
	int evtchn = evtchn_from_irq(irq);
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	int rc;
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	BUG_ON(info->type != IRQT_PIRQ);

	if (VALID_EVTCHN(evtchn))
		goto out;

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	bind_pirq.pirq = pirq_from_irq(irq);
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	/* NB. We are happy to share unless we are probing. */
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	bind_pirq.flags = info->u.pirq.flags & PIRQ_SHAREABLE ?
					BIND_PIRQ__WILL_SHARE : 0;
	rc = HYPERVISOR_event_channel_op(EVTCHNOP_bind_pirq, &bind_pirq);
	if (rc != 0) {
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		if (!probing_irq(irq))
			printk(KERN_INFO "Failed to obtain physical IRQ %d\n",
			       irq);
		return 0;
	}
	evtchn = bind_pirq.port;

	pirq_query_unmask(irq);

	evtchn_to_irq[evtchn] = irq;
	bind_evtchn_to_cpu(evtchn, 0);
	info->evtchn = evtchn;

out:
	unmask_evtchn(evtchn);
	pirq_unmask_notify(irq);

	return 0;
}

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static unsigned int startup_pirq(struct irq_data *data)
{
	return __startup_pirq(data->irq);
}

static void shutdown_pirq(struct irq_data *data)
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{
	struct evtchn_close close;
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	unsigned int irq = data->irq;
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	struct irq_info *info = info_for_irq(irq);
	int evtchn = evtchn_from_irq(irq);

	BUG_ON(info->type != IRQT_PIRQ);

	if (!VALID_EVTCHN(evtchn))
		return;

	mask_evtchn(evtchn);

	close.port = evtchn;
	if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0)
		BUG();

	bind_evtchn_to_cpu(evtchn, 0);
	evtchn_to_irq[evtchn] = -1;
	info->evtchn = 0;
}

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static void enable_pirq(struct irq_data *data)
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{
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	startup_pirq(data);
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}

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static void disable_pirq(struct irq_data *data)
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{
}

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static void ack_pirq(struct irq_data *data)
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{
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	int evtchn = evtchn_from_irq(data->irq);
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	move_native_irq(data->irq);
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	if (VALID_EVTCHN(evtchn)) {
		mask_evtchn(evtchn);
		clear_evtchn(evtchn);
	}
}

static int find_irq_by_gsi(unsigned gsi)
{
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	struct irq_info *info;
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	list_for_each_entry(info, &xen_irq_list_head, list) {
		if (info->type != IRQT_PIRQ)
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			continue;

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		if (info->u.pirq.gsi == gsi)
			return info->irq;
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	}

	return -1;
}

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int xen_allocate_pirq_gsi(unsigned gsi)
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{
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	return gsi;
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}

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/*
 * Do not make any assumptions regarding the relationship between the
 * IRQ number returned here and the Xen pirq argument.
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 *
 * Note: We don't assign an event channel until the irq actually started
 * up.  Return an existing irq if we've already got one for the gsi.
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 */
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int xen_bind_pirq_gsi_to_irq(unsigned gsi,
			     unsigned pirq, int shareable, char *name)
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{
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	int irq = -1;
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	struct physdev_irq irq_op;

	spin_lock(&irq_mapping_update_lock);

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	if ((pirq > nr_irqs) || (gsi > nr_irqs)) {
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		printk(KERN_WARNING "xen_map_pirq_gsi: %s %s is incorrect!\n",
654 655
			pirq > nr_irqs ? "pirq" :"",
			gsi > nr_irqs ? "gsi" : "");
656 657 658
		goto out;
	}

659 660
	irq = find_irq_by_gsi(gsi);
	if (irq != -1) {
661
		printk(KERN_INFO "xen_map_pirq_gsi: returning irq %d for gsi %u\n",
662 663 664 665
		       irq, gsi);
		goto out;	/* XXX need refcount? */
	}

666
	irq = xen_allocate_irq_gsi(gsi);
667 668

	set_irq_chip_and_handler_name(irq, &xen_pirq_chip,
669
				      handle_level_irq, name);
670 671

	irq_op.irq = irq;
672 673 674 675 676 677 678
	irq_op.vector = 0;

	/* Only the privileged domain can do this. For non-priv, the pcifront
	 * driver provides a PCI bus that does the call to do exactly
	 * this in the priv domain. */
	if (xen_initial_domain() &&
	    HYPERVISOR_physdev_op(PHYSDEVOP_alloc_irq_vector, &irq_op)) {
679
		xen_free_irq(irq);
680 681 682 683
		irq = -ENOSPC;
		goto out;
	}

684 685
	xen_irq_info_pirq_init(irq, 0, pirq, gsi, irq_op.vector,
			       shareable ? PIRQ_SHAREABLE : 0);
686 687 688 689 690 691 692

out:
	spin_unlock(&irq_mapping_update_lock);

	return irq;
}

693
#ifdef CONFIG_PCI_MSI
694
int xen_allocate_pirq_msi(struct pci_dev *dev, struct msi_desc *msidesc)
695
{
696
	int rc;
697 698
	struct physdev_get_free_pirq op_get_free_pirq;

699
	op_get_free_pirq.type = MAP_PIRQ_TYPE_MSI;
700 701
	rc = HYPERVISOR_physdev_op(PHYSDEVOP_get_free_pirq, &op_get_free_pirq);

702 703 704 705
	WARN_ONCE(rc == -ENOSYS,
		  "hypervisor does not support the PHYSDEVOP_get_free_pirq interface\n");

	return rc ? -1 : op_get_free_pirq.pirq;
706 707
}

708
int xen_bind_pirq_msi_to_irq(struct pci_dev *dev, struct msi_desc *msidesc,
709
			     int pirq, int vector, const char *name)
710
{
711
	int irq, ret;
712

713 714
	spin_lock(&irq_mapping_update_lock);

715 716
	irq = xen_allocate_irq_dynamic();
	if (irq == -1)
717
		goto out;
718

719
	set_irq_chip_and_handler_name(irq, &xen_pirq_chip,
720 721
				      handle_level_irq, name);

722
	xen_irq_info_pirq_init(irq, 0, pirq, 0, vector, 0);
723 724 725
	ret = set_irq_msi(irq, msidesc);
	if (ret < 0)
		goto error_irq;
726 727
out:
	spin_unlock(&irq_mapping_update_lock);
728
	return irq;
729 730 731 732
error_irq:
	spin_unlock(&irq_mapping_update_lock);
	xen_free_irq(irq);
	return -1;
733
}
734 735
#endif

736 737 738
int xen_destroy_irq(int irq)
{
	struct irq_desc *desc;
739 740
	struct physdev_unmap_pirq unmap_irq;
	struct irq_info *info = info_for_irq(irq);
741 742 743 744 745 746 747 748
	int rc = -ENOENT;

	spin_lock(&irq_mapping_update_lock);

	desc = irq_to_desc(irq);
	if (!desc)
		goto out;

749
	if (xen_initial_domain()) {
750
		unmap_irq.pirq = info->u.pirq.pirq;
751 752 753 754 755 756 757
		unmap_irq.domid = DOMID_SELF;
		rc = HYPERVISOR_physdev_op(PHYSDEVOP_unmap_pirq, &unmap_irq);
		if (rc) {
			printk(KERN_WARNING "unmap irq failed %d\n", rc);
			goto out;
		}
	}
758 759
	pirq_to_irq[info->u.pirq.pirq] = -1;

760
	xen_free_irq(irq);
761 762 763 764 765 766

out:
	spin_unlock(&irq_mapping_update_lock);
	return rc;
}

767 768 769 770 771
int xen_irq_from_pirq(unsigned pirq)
{
	return pirq_to_irq[pirq];
}

772
int bind_evtchn_to_irq(unsigned int evtchn)
J
Jeremy Fitzhardinge 已提交
773 774 775 776 777 778 779 780
{
	int irq;

	spin_lock(&irq_mapping_update_lock);

	irq = evtchn_to_irq[evtchn];

	if (irq == -1) {
781
		irq = xen_allocate_irq_dynamic();
J
Jeremy Fitzhardinge 已提交
782 783

		set_irq_chip_and_handler_name(irq, &xen_dynamic_chip,
784
					      handle_fasteoi_irq, "event");
J
Jeremy Fitzhardinge 已提交
785

786
		xen_irq_info_evtchn_init(irq, evtchn);
J
Jeremy Fitzhardinge 已提交
787 788 789 790 791 792
	}

	spin_unlock(&irq_mapping_update_lock);

	return irq;
}
793
EXPORT_SYMBOL_GPL(bind_evtchn_to_irq);
J
Jeremy Fitzhardinge 已提交
794

795 796 797 798 799 800 801 802
static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu)
{
	struct evtchn_bind_ipi bind_ipi;
	int evtchn, irq;

	spin_lock(&irq_mapping_update_lock);

	irq = per_cpu(ipi_to_irq, cpu)[ipi];
803

804
	if (irq == -1) {
805
		irq = xen_allocate_irq_dynamic();
806 807 808
		if (irq < 0)
			goto out;

809 810
		set_irq_chip_and_handler_name(irq, &xen_percpu_chip,
					      handle_percpu_irq, "ipi");
811 812 813 814 815 816 817

		bind_ipi.vcpu = cpu;
		if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi,
						&bind_ipi) != 0)
			BUG();
		evtchn = bind_ipi.port;

818
		xen_irq_info_ipi_init(cpu, irq, evtchn, ipi);
819 820 821 822 823 824 825 826 827 828

		bind_evtchn_to_cpu(evtchn, cpu);
	}

 out:
	spin_unlock(&irq_mapping_update_lock);
	return irq;
}


829
int bind_virq_to_irq(unsigned int virq, unsigned int cpu)
J
Jeremy Fitzhardinge 已提交
830 831 832 833 834 835 836 837 838
{
	struct evtchn_bind_virq bind_virq;
	int evtchn, irq;

	spin_lock(&irq_mapping_update_lock);

	irq = per_cpu(virq_to_irq, cpu)[virq];

	if (irq == -1) {
839
		irq = xen_allocate_irq_dynamic();
840 841 842 843

		set_irq_chip_and_handler_name(irq, &xen_percpu_chip,
					      handle_percpu_irq, "virq");

J
Jeremy Fitzhardinge 已提交
844 845 846 847 848 849 850
		bind_virq.virq = virq;
		bind_virq.vcpu = cpu;
		if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq,
						&bind_virq) != 0)
			BUG();
		evtchn = bind_virq.port;

851
		xen_irq_info_virq_init(cpu, irq, evtchn, virq);
J
Jeremy Fitzhardinge 已提交
852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867

		bind_evtchn_to_cpu(evtchn, cpu);
	}

	spin_unlock(&irq_mapping_update_lock);

	return irq;
}

static void unbind_from_irq(unsigned int irq)
{
	struct evtchn_close close;
	int evtchn = evtchn_from_irq(irq);

	spin_lock(&irq_mapping_update_lock);

868
	if (VALID_EVTCHN(evtchn)) {
J
Jeremy Fitzhardinge 已提交
869 870 871 872 873 874 875
		close.port = evtchn;
		if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0)
			BUG();

		switch (type_from_irq(irq)) {
		case IRQT_VIRQ:
			per_cpu(virq_to_irq, cpu_from_evtchn(evtchn))
876
				[virq_from_irq(irq)] = -1;
J
Jeremy Fitzhardinge 已提交
877
			break;
878 879
		case IRQT_IPI:
			per_cpu(ipi_to_irq, cpu_from_evtchn(evtchn))
880
				[ipi_from_irq(irq)] = -1;
881
			break;
J
Jeremy Fitzhardinge 已提交
882 883 884 885 886 887 888 889
		default:
			break;
		}

		/* Closed ports are implicitly re-bound to VCPU0. */
		bind_evtchn_to_cpu(evtchn, 0);

		evtchn_to_irq[evtchn] = -1;
890 891
	}

892
	BUG_ON(irq_info[irq].type == IRQT_UNBOUND);
J
Jeremy Fitzhardinge 已提交
893

894
	xen_free_irq(irq);
J
Jeremy Fitzhardinge 已提交
895 896 897 898 899

	spin_unlock(&irq_mapping_update_lock);
}

int bind_evtchn_to_irqhandler(unsigned int evtchn,
900
			      irq_handler_t handler,
J
Jeremy Fitzhardinge 已提交
901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918
			      unsigned long irqflags,
			      const char *devname, void *dev_id)
{
	unsigned int irq;
	int retval;

	irq = bind_evtchn_to_irq(evtchn);
	retval = request_irq(irq, handler, irqflags, devname, dev_id);
	if (retval != 0) {
		unbind_from_irq(irq);
		return retval;
	}

	return irq;
}
EXPORT_SYMBOL_GPL(bind_evtchn_to_irqhandler);

int bind_virq_to_irqhandler(unsigned int virq, unsigned int cpu,
919
			    irq_handler_t handler,
J
Jeremy Fitzhardinge 已提交
920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935
			    unsigned long irqflags, const char *devname, void *dev_id)
{
	unsigned int irq;
	int retval;

	irq = bind_virq_to_irq(virq, cpu);
	retval = request_irq(irq, handler, irqflags, devname, dev_id);
	if (retval != 0) {
		unbind_from_irq(irq);
		return retval;
	}

	return irq;
}
EXPORT_SYMBOL_GPL(bind_virq_to_irqhandler);

936 937 938 939 940 941 942 943 944 945 946 947 948
int bind_ipi_to_irqhandler(enum ipi_vector ipi,
			   unsigned int cpu,
			   irq_handler_t handler,
			   unsigned long irqflags,
			   const char *devname,
			   void *dev_id)
{
	int irq, retval;

	irq = bind_ipi_to_irq(ipi, cpu);
	if (irq < 0)
		return irq;

949
	irqflags |= IRQF_NO_SUSPEND | IRQF_FORCE_RESUME;
950 951 952 953 954 955 956 957 958
	retval = request_irq(irq, handler, irqflags, devname, dev_id);
	if (retval != 0) {
		unbind_from_irq(irq);
		return retval;
	}

	return irq;
}

J
Jeremy Fitzhardinge 已提交
959 960 961 962 963 964 965
void unbind_from_irqhandler(unsigned int irq, void *dev_id)
{
	free_irq(irq, dev_id);
	unbind_from_irq(irq);
}
EXPORT_SYMBOL_GPL(unbind_from_irqhandler);

966 967 968 969 970 971 972
void xen_send_IPI_one(unsigned int cpu, enum ipi_vector vector)
{
	int irq = per_cpu(ipi_to_irq, cpu)[vector];
	BUG_ON(irq < 0);
	notify_remote_via_irq(irq);
}

973 974 975 976
irqreturn_t xen_debug_interrupt(int irq, void *dev_id)
{
	struct shared_info *sh = HYPERVISOR_shared_info;
	int cpu = smp_processor_id();
977
	unsigned long *cpu_evtchn = per_cpu(cpu_evtchn_mask, cpu);
978 979 980
	int i;
	unsigned long flags;
	static DEFINE_SPINLOCK(debug_lock);
981
	struct vcpu_info *v;
982 983 984

	spin_lock_irqsave(&debug_lock, flags);

985
	printk("\nvcpu %d\n  ", cpu);
986 987

	for_each_online_cpu(i) {
988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030
		int pending;
		v = per_cpu(xen_vcpu, i);
		pending = (get_irq_regs() && i == cpu)
			? xen_irqs_disabled(get_irq_regs())
			: v->evtchn_upcall_mask;
		printk("%d: masked=%d pending=%d event_sel %0*lx\n  ", i,
		       pending, v->evtchn_upcall_pending,
		       (int)(sizeof(v->evtchn_pending_sel)*2),
		       v->evtchn_pending_sel);
	}
	v = per_cpu(xen_vcpu, cpu);

	printk("\npending:\n   ");
	for (i = ARRAY_SIZE(sh->evtchn_pending)-1; i >= 0; i--)
		printk("%0*lx%s", (int)sizeof(sh->evtchn_pending[0])*2,
		       sh->evtchn_pending[i],
		       i % 8 == 0 ? "\n   " : " ");
	printk("\nglobal mask:\n   ");
	for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--)
		printk("%0*lx%s",
		       (int)(sizeof(sh->evtchn_mask[0])*2),
		       sh->evtchn_mask[i],
		       i % 8 == 0 ? "\n   " : " ");

	printk("\nglobally unmasked:\n   ");
	for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--)
		printk("%0*lx%s", (int)(sizeof(sh->evtchn_mask[0])*2),
		       sh->evtchn_pending[i] & ~sh->evtchn_mask[i],
		       i % 8 == 0 ? "\n   " : " ");

	printk("\nlocal cpu%d mask:\n   ", cpu);
	for (i = (NR_EVENT_CHANNELS/BITS_PER_LONG)-1; i >= 0; i--)
		printk("%0*lx%s", (int)(sizeof(cpu_evtchn[0])*2),
		       cpu_evtchn[i],
		       i % 8 == 0 ? "\n   " : " ");

	printk("\nlocally unmasked:\n   ");
	for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--) {
		unsigned long pending = sh->evtchn_pending[i]
			& ~sh->evtchn_mask[i]
			& cpu_evtchn[i];
		printk("%0*lx%s", (int)(sizeof(sh->evtchn_mask[0])*2),
		       pending, i % 8 == 0 ? "\n   " : " ");
1031 1032 1033
	}

	printk("\npending list:\n");
1034
	for (i = 0; i < NR_EVENT_CHANNELS; i++) {
1035
		if (sync_test_bit(i, sh->evtchn_pending)) {
1036 1037
			int word_idx = i / BITS_PER_LONG;
			printk("  %d: event %d -> irq %d%s%s%s\n",
1038
			       cpu_from_evtchn(i), i,
1039 1040 1041 1042 1043 1044 1045
			       evtchn_to_irq[i],
			       sync_test_bit(word_idx, &v->evtchn_pending_sel)
					     ? "" : " l2-clear",
			       !sync_test_bit(i, sh->evtchn_mask)
					     ? "" : " globally-masked",
			       sync_test_bit(i, cpu_evtchn)
					     ? "" : " locally-masked");
1046 1047 1048 1049 1050 1051 1052 1053
		}
	}

	spin_unlock_irqrestore(&debug_lock, flags);

	return IRQ_HANDLED;
}

1054 1055
static DEFINE_PER_CPU(unsigned, xed_nesting_count);

J
Jeremy Fitzhardinge 已提交
1056 1057 1058 1059 1060 1061 1062 1063 1064
/*
 * Search the CPUs pending events bitmasks.  For each one found, map
 * the event number to an irq, and feed it into do_IRQ() for
 * handling.
 *
 * Xen uses a two-level bitmap to speed searching.  The first level is
 * a bitset of words which contain pending event bits.  The second
 * level is a bitset of pending events themselves.
 */
1065
static void __xen_evtchn_do_upcall(void)
J
Jeremy Fitzhardinge 已提交
1066 1067 1068
{
	int cpu = get_cpu();
	struct shared_info *s = HYPERVISOR_shared_info;
C
Christoph Lameter 已提交
1069
	struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu);
1070
 	unsigned count;
J
Jeremy Fitzhardinge 已提交
1071

1072 1073
	do {
		unsigned long pending_words;
J
Jeremy Fitzhardinge 已提交
1074

1075
		vcpu_info->evtchn_upcall_pending = 0;
J
Jeremy Fitzhardinge 已提交
1076

1077
		if (__this_cpu_inc_return(xed_nesting_count) - 1)
1078
			goto out;
J
Jeremy Fitzhardinge 已提交
1079

1080 1081
#ifndef CONFIG_X86 /* No need for a barrier -- XCHG is a barrier on x86. */
		/* Clear master flag /before/ clearing selector flag. */
1082
		wmb();
1083
#endif
1084 1085 1086 1087 1088 1089 1090 1091 1092 1093
		pending_words = xchg(&vcpu_info->evtchn_pending_sel, 0);
		while (pending_words != 0) {
			unsigned long pending_bits;
			int word_idx = __ffs(pending_words);
			pending_words &= ~(1UL << word_idx);

			while ((pending_bits = active_evtchns(cpu, s, word_idx)) != 0) {
				int bit_idx = __ffs(pending_bits);
				int port = (word_idx * BITS_PER_LONG) + bit_idx;
				int irq = evtchn_to_irq[port];
1094
				struct irq_desc *desc;
1095

1096 1097 1098
				mask_evtchn(port);
				clear_evtchn(port);

1099 1100 1101 1102 1103
				if (irq != -1) {
					desc = irq_to_desc(irq);
					if (desc)
						generic_handle_irq_desc(irq, desc);
				}
J
Jeremy Fitzhardinge 已提交
1104 1105 1106
			}
		}

1107 1108
		BUG_ON(!irqs_disabled());

C
Christoph Lameter 已提交
1109 1110
		count = __this_cpu_read(xed_nesting_count);
		__this_cpu_write(xed_nesting_count, 0);
1111
	} while (count != 1 || vcpu_info->evtchn_upcall_pending);
1112 1113

out:
1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126

	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();

1127 1128
	irq_exit();
	set_irq_regs(old_regs);
1129
}
1130

1131 1132 1133
void xen_hvm_evtchn_do_upcall(void)
{
	__xen_evtchn_do_upcall();
J
Jeremy Fitzhardinge 已提交
1134
}
1135
EXPORT_SYMBOL_GPL(xen_hvm_evtchn_do_upcall);
J
Jeremy Fitzhardinge 已提交
1136

1137 1138 1139
/* Rebind a new event channel to an existing irq. */
void rebind_evtchn_irq(int evtchn, int irq)
{
1140 1141
	struct irq_info *info = info_for_irq(irq);

1142 1143 1144 1145 1146 1147 1148 1149 1150
	/* Make sure the irq is masked, since the new event channel
	   will also be masked. */
	disable_irq(irq);

	spin_lock(&irq_mapping_update_lock);

	/* After resume the irq<->evtchn mappings are all cleared out */
	BUG_ON(evtchn_to_irq[evtchn] != -1);
	/* Expect irq to have been bound before,
1151 1152
	   so there should be a proper type */
	BUG_ON(info->type == IRQT_UNBOUND);
1153

1154
	xen_irq_info_evtchn_init(irq, evtchn);
1155 1156 1157 1158

	spin_unlock(&irq_mapping_update_lock);

	/* new event channels are always bound to cpu 0 */
1159
	irq_set_affinity(irq, cpumask_of(0));
1160 1161 1162 1163 1164

	/* Unmask the event channel. */
	enable_irq(irq);
}

J
Jeremy Fitzhardinge 已提交
1165
/* Rebind an evtchn so that it gets delivered to a specific cpu */
1166
static int rebind_irq_to_cpu(unsigned irq, unsigned tcpu)
J
Jeremy Fitzhardinge 已提交
1167 1168 1169 1170
{
	struct evtchn_bind_vcpu bind_vcpu;
	int evtchn = evtchn_from_irq(irq);

1171 1172 1173 1174 1175 1176 1177 1178
	if (!VALID_EVTCHN(evtchn))
		return -1;

	/*
	 * Events delivered via platform PCI interrupts are always
	 * routed to vcpu 0 and hence cannot be rebound.
	 */
	if (xen_hvm_domain() && !xen_have_vector_callback)
1179
		return -1;
J
Jeremy Fitzhardinge 已提交
1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192

	/* Send future instances of this interrupt to other vcpu. */
	bind_vcpu.port = evtchn;
	bind_vcpu.vcpu = tcpu;

	/*
	 * If this fails, it usually just indicates that we're dealing with a
	 * virq or IPI channel, which don't actually need to be rebound. Ignore
	 * it, but don't do the xenlinux-level rebind in that case.
	 */
	if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_vcpu, &bind_vcpu) >= 0)
		bind_evtchn_to_cpu(evtchn, tcpu);

1193 1194
	return 0;
}
J
Jeremy Fitzhardinge 已提交
1195

1196 1197
static int set_affinity_irq(struct irq_data *data, const struct cpumask *dest,
			    bool force)
J
Jeremy Fitzhardinge 已提交
1198
{
1199
	unsigned tcpu = cpumask_first(dest);
1200

1201
	return rebind_irq_to_cpu(data->irq, tcpu);
J
Jeremy Fitzhardinge 已提交
1202 1203
}

1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219
int resend_irq_on_evtchn(unsigned int irq)
{
	int masked, evtchn = evtchn_from_irq(irq);
	struct shared_info *s = HYPERVISOR_shared_info;

	if (!VALID_EVTCHN(evtchn))
		return 1;

	masked = sync_test_and_set_bit(evtchn, s->evtchn_mask);
	sync_set_bit(evtchn, s->evtchn_pending);
	if (!masked)
		unmask_evtchn(evtchn);

	return 1;
}

1220
static void enable_dynirq(struct irq_data *data)
J
Jeremy Fitzhardinge 已提交
1221
{
1222
	int evtchn = evtchn_from_irq(data->irq);
J
Jeremy Fitzhardinge 已提交
1223 1224 1225 1226 1227

	if (VALID_EVTCHN(evtchn))
		unmask_evtchn(evtchn);
}

1228
static void disable_dynirq(struct irq_data *data)
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{
1230
	int evtchn = evtchn_from_irq(data->irq);
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	if (VALID_EVTCHN(evtchn))
		mask_evtchn(evtchn);
}

1236
static void ack_dynirq(struct irq_data *data)
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{
1238
	int evtchn = evtchn_from_irq(data->irq);
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1240
	move_masked_irq(data->irq);
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	if (VALID_EVTCHN(evtchn))
1243
		unmask_evtchn(evtchn);
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}

1246
static int retrigger_dynirq(struct irq_data *data)
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{
1248
	int evtchn = evtchn_from_irq(data->irq);
1249
	struct shared_info *sh = HYPERVISOR_shared_info;
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	int ret = 0;

	if (VALID_EVTCHN(evtchn)) {
1253 1254 1255 1256 1257 1258
		int masked;

		masked = sync_test_and_set_bit(evtchn, sh->evtchn_mask);
		sync_set_bit(evtchn, sh->evtchn_pending);
		if (!masked)
			unmask_evtchn(evtchn);
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		ret = 1;
	}

	return ret;
}

1265
static void restore_pirqs(void)
1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289
{
	int pirq, rc, irq, gsi;
	struct physdev_map_pirq map_irq;

	for (pirq = 0; pirq < nr_irqs; pirq++) {
		irq = pirq_to_irq[pirq];
		if (irq == -1)
			continue;

		/* save/restore of PT devices doesn't work, so at this point the
		 * only devices present are GSI based emulated devices */
		gsi = gsi_from_irq(irq);
		if (!gsi)
			continue;

		map_irq.domid = DOMID_SELF;
		map_irq.type = MAP_PIRQ_TYPE_GSI;
		map_irq.index = gsi;
		map_irq.pirq = pirq;

		rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
		if (rc) {
			printk(KERN_WARNING "xen map irq failed gsi=%d irq=%d pirq=%d rc=%d\n",
					gsi, irq, pirq, rc);
1290
			xen_free_irq(irq);
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			pirq_to_irq[pirq] = -1;
			continue;
		}

		printk(KERN_DEBUG "xen: --> irq=%d, pirq=%d\n", irq, map_irq.pirq);

1297
		__startup_pirq(irq);
1298 1299 1300
	}
}

1301 1302 1303 1304 1305 1306 1307 1308 1309
static void restore_cpu_virqs(unsigned int cpu)
{
	struct evtchn_bind_virq bind_virq;
	int virq, irq, evtchn;

	for (virq = 0; virq < NR_VIRQS; virq++) {
		if ((irq = per_cpu(virq_to_irq, cpu)[virq]) == -1)
			continue;

1310
		BUG_ON(virq_from_irq(irq) != virq);
1311 1312 1313 1314 1315 1316 1317 1318 1319 1320

		/* Get a new binding from Xen. */
		bind_virq.virq = virq;
		bind_virq.vcpu = cpu;
		if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq,
						&bind_virq) != 0)
			BUG();
		evtchn = bind_virq.port;

		/* Record the new mapping. */
1321
		xen_irq_info_virq_init(cpu, irq, evtchn, virq);
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		bind_evtchn_to_cpu(evtchn, cpu);
	}
}

static void restore_cpu_ipis(unsigned int cpu)
{
	struct evtchn_bind_ipi bind_ipi;
	int ipi, irq, evtchn;

	for (ipi = 0; ipi < XEN_NR_IPIS; ipi++) {
		if ((irq = per_cpu(ipi_to_irq, cpu)[ipi]) == -1)
			continue;

1335
		BUG_ON(ipi_from_irq(irq) != ipi);
1336 1337 1338 1339 1340 1341 1342 1343 1344

		/* Get a new binding from Xen. */
		bind_ipi.vcpu = cpu;
		if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi,
						&bind_ipi) != 0)
			BUG();
		evtchn = bind_ipi.port;

		/* Record the new mapping. */
1345
		xen_irq_info_ipi_init(cpu, irq, evtchn, ipi);
1346 1347 1348 1349
		bind_evtchn_to_cpu(evtchn, cpu);
	}
}

1350 1351 1352 1353 1354 1355 1356 1357
/* Clear an irq's pending state, in preparation for polling on it */
void xen_clear_irq_pending(int irq)
{
	int evtchn = evtchn_from_irq(irq);

	if (VALID_EVTCHN(evtchn))
		clear_evtchn(evtchn);
}
1358
EXPORT_SYMBOL(xen_clear_irq_pending);
1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377
void xen_set_irq_pending(int irq)
{
	int evtchn = evtchn_from_irq(irq);

	if (VALID_EVTCHN(evtchn))
		set_evtchn(evtchn);
}

bool xen_test_irq_pending(int irq)
{
	int evtchn = evtchn_from_irq(irq);
	bool ret = false;

	if (VALID_EVTCHN(evtchn))
		ret = test_evtchn(evtchn);

	return ret;
}

1378 1379 1380
/* Poll waiting for an irq to become pending with timeout.  In the usual case,
 * the irq will be disabled so it won't deliver an interrupt. */
void xen_poll_irq_timeout(int irq, u64 timeout)
1381 1382 1383 1384 1385 1386 1387
{
	evtchn_port_t evtchn = evtchn_from_irq(irq);

	if (VALID_EVTCHN(evtchn)) {
		struct sched_poll poll;

		poll.nr_ports = 1;
1388
		poll.timeout = timeout;
1389
		set_xen_guest_handle(poll.ports, &evtchn);
1390 1391 1392 1393 1394

		if (HYPERVISOR_sched_op(SCHEDOP_poll, &poll) != 0)
			BUG();
	}
}
1395 1396 1397 1398 1399 1400 1401
EXPORT_SYMBOL(xen_poll_irq_timeout);
/* Poll waiting for an irq to become pending.  In the usual case, the
 * irq will be disabled so it won't deliver an interrupt. */
void xen_poll_irq(int irq)
{
	xen_poll_irq_timeout(irq, 0 /* no timeout */);
}
1402

1403 1404
void xen_irq_resume(void)
{
1405 1406
	unsigned int cpu, evtchn;
	struct irq_info *info;
1407 1408 1409 1410 1411 1412 1413 1414

	init_evtchn_cpu_bindings();

	/* New event-channel space is not 'live' yet. */
	for (evtchn = 0; evtchn < NR_EVENT_CHANNELS; evtchn++)
		mask_evtchn(evtchn);

	/* No IRQ <-> event-channel mappings. */
1415 1416
	list_for_each_entry(info, &xen_irq_list_head, list)
		info->evtchn = 0; /* zap event-channel binding */
1417 1418 1419 1420 1421 1422 1423 1424

	for (evtchn = 0; evtchn < NR_EVENT_CHANNELS; evtchn++)
		evtchn_to_irq[evtchn] = -1;

	for_each_possible_cpu(cpu) {
		restore_cpu_virqs(cpu);
		restore_cpu_ipis(cpu);
	}
1425

1426
	restore_pirqs();
1427 1428
}

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static struct irq_chip xen_dynamic_chip __read_mostly = {
1430
	.name			= "xen-dyn",
1431

1432 1433 1434
	.irq_disable		= disable_dynirq,
	.irq_mask		= disable_dynirq,
	.irq_unmask		= enable_dynirq,
1435

1436 1437 1438
	.irq_eoi		= ack_dynirq,
	.irq_set_affinity	= set_affinity_irq,
	.irq_retrigger		= retrigger_dynirq,
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};

1441
static struct irq_chip xen_pirq_chip __read_mostly = {
1442
	.name			= "xen-pirq",
1443

1444 1445
	.irq_startup		= startup_pirq,
	.irq_shutdown		= shutdown_pirq,
1446

1447 1448
	.irq_enable		= enable_pirq,
	.irq_unmask		= enable_pirq,
1449

1450 1451
	.irq_disable		= disable_pirq,
	.irq_mask		= disable_pirq,
1452

1453
	.irq_ack		= ack_pirq,
1454

1455
	.irq_set_affinity	= set_affinity_irq,
1456

1457
	.irq_retrigger		= retrigger_dynirq,
1458 1459
};

1460
static struct irq_chip xen_percpu_chip __read_mostly = {
1461
	.name			= "xen-percpu",
1462

1463 1464 1465
	.irq_disable		= disable_dynirq,
	.irq_mask		= disable_dynirq,
	.irq_unmask		= enable_dynirq,
1466

1467
	.irq_ack		= ack_dynirq,
1468 1469
};

1470 1471 1472 1473 1474 1475 1476 1477 1478 1479
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);

1480
#ifdef CONFIG_XEN_PVHVM
1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503
/* 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);
	}
}
1504 1505 1506
#else
void xen_callback_vector(void) {}
#endif
1507

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void __init xen_init_IRQ(void)
{
1510
	int i;
1511

1512 1513
	irq_info = kcalloc(nr_irqs, sizeof(*irq_info), GFP_KERNEL);

1514 1515 1516 1517 1518
	/* We are using nr_irqs as the maximum number of pirq available but
	 * that number is actually chosen by Xen and we don't know exactly
	 * what it is. Be careful choosing high pirq numbers. */
	pirq_to_irq = kcalloc(nr_irqs, sizeof(*pirq_to_irq), GFP_KERNEL);
	for (i = 0; i < nr_irqs; i++)
1519 1520
		pirq_to_irq[i] = -1;

1521 1522 1523 1524
	evtchn_to_irq = kcalloc(NR_EVENT_CHANNELS, sizeof(*evtchn_to_irq),
				    GFP_KERNEL);
	for (i = 0; i < NR_EVENT_CHANNELS; i++)
		evtchn_to_irq[i] = -1;
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	init_evtchn_cpu_bindings();

	/* No event channels are 'live' right now. */
	for (i = 0; i < NR_EVENT_CHANNELS; i++)
		mask_evtchn(i);

1532 1533 1534
	if (xen_hvm_domain()) {
		xen_callback_vector();
		native_init_IRQ();
1535 1536 1537
		/* pci_xen_hvm_init must be called after native_init_IRQ so that
		 * __acpi_register_gsi can point at the right function */
		pci_xen_hvm_init();
1538 1539
	} else {
		irq_ctx_init(smp_processor_id());
1540 1541
		if (xen_initial_domain())
			xen_setup_pirqs();
1542
	}
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}
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