mirror of https://gitee.com/openkylin/linux.git
947 lines
21 KiB
C
947 lines
21 KiB
C
/*
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* Xen event channels
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*
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* Xen models interrupts with abstract event channels. Because each
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* domain gets 1024 event channels, but NR_IRQ is not that large, we
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* must dynamically map irqs<->event channels. The event channels
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* interface with the rest of the kernel by defining a xen interrupt
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* chip. When an event is recieved, it is mapped to an irq and sent
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* through the normal interrupt processing path.
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*
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* There are four kinds of events which can be mapped to an event
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* channel:
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*
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* 1. Inter-domain notifications. This includes all the virtual
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* device events, since they're driven by front-ends in another domain
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* (typically dom0).
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* 2. VIRQs, typically used for timers. These are per-cpu events.
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* 3. IPIs.
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* 4. Hardware interrupts. Not supported at present.
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*
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* Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
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*/
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#include <linux/linkage.h>
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#include <linux/interrupt.h>
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#include <linux/irq.h>
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#include <linux/module.h>
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#include <linux/string.h>
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#include <linux/bootmem.h>
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#include <asm/ptrace.h>
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#include <asm/irq.h>
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#include <asm/idle.h>
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#include <asm/sync_bitops.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-ops.h>
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#include <xen/events.h>
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#include <xen/interface/xen.h>
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#include <xen/interface/event_channel.h>
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/*
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* This lock protects updates to the following mapping and reference-count
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* arrays. The lock does not need to be acquired to read the mapping tables.
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*/
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static DEFINE_SPINLOCK(irq_mapping_update_lock);
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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. */
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enum xen_irq_type {
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IRQT_UNBOUND = 0,
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IRQT_PIRQ,
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IRQT_VIRQ,
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IRQT_IPI,
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IRQT_EVTCHN
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};
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/*
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* Packed IRQ information:
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* type - enum xen_irq_type
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* event channel - irq->event channel mapping
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* cpu - cpu this event channel is bound to
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* index - type-specific information:
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* PIRQ - vector, with MSB being "needs EIO"
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* VIRQ - virq number
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* IPI - IPI vector
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* EVTCHN -
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*/
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struct irq_info
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{
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enum xen_irq_type type; /* type */
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unsigned short evtchn; /* event channel */
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unsigned short cpu; /* cpu bound */
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union {
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unsigned short virq;
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enum ipi_vector ipi;
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struct {
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unsigned short gsi;
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unsigned short vector;
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} pirq;
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} u;
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};
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static struct irq_info irq_info[NR_IRQS];
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static int evtchn_to_irq[NR_EVENT_CHANNELS] = {
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[0 ... NR_EVENT_CHANNELS-1] = -1
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};
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struct cpu_evtchn_s {
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unsigned long bits[NR_EVENT_CHANNELS/BITS_PER_LONG];
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};
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static struct cpu_evtchn_s *cpu_evtchn_mask_p;
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static inline unsigned long *cpu_evtchn_mask(int cpu)
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{
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return cpu_evtchn_mask_p[cpu].bits;
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}
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/* Xen will never allocate port zero for any purpose. */
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#define VALID_EVTCHN(chn) ((chn) != 0)
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static struct irq_chip xen_dynamic_chip;
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/* Constructor for packed IRQ information. */
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static struct irq_info mk_unbound_info(void)
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{
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return (struct irq_info) { .type = IRQT_UNBOUND };
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}
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static struct irq_info mk_evtchn_info(unsigned short evtchn)
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{
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return (struct irq_info) { .type = IRQT_EVTCHN, .evtchn = evtchn,
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.cpu = 0 };
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}
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static struct irq_info mk_ipi_info(unsigned short evtchn, enum ipi_vector ipi)
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{
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return (struct irq_info) { .type = IRQT_IPI, .evtchn = evtchn,
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.cpu = 0, .u.ipi = ipi };
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}
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static struct irq_info mk_virq_info(unsigned short evtchn, unsigned short virq)
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{
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return (struct irq_info) { .type = IRQT_VIRQ, .evtchn = evtchn,
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.cpu = 0, .u.virq = virq };
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}
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static struct irq_info mk_pirq_info(unsigned short evtchn,
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unsigned short gsi, unsigned short vector)
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{
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return (struct irq_info) { .type = IRQT_PIRQ, .evtchn = evtchn,
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.cpu = 0, .u.pirq = { .gsi = gsi, .vector = vector } };
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}
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/*
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* Accessors for packed IRQ information.
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*/
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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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static unsigned int evtchn_from_irq(unsigned irq)
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{
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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)
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{
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return evtchn_to_irq[evtchn];
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}
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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);
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BUG_ON(info == NULL);
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BUG_ON(info->type != IRQT_IPI);
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return info->u.ipi;
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}
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static unsigned virq_from_irq(unsigned irq)
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{
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struct irq_info *info = info_for_irq(irq);
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BUG_ON(info == NULL);
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BUG_ON(info->type != IRQT_VIRQ);
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return info->u.virq;
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}
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static unsigned gsi_from_irq(unsigned irq)
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{
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struct irq_info *info = info_for_irq(irq);
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BUG_ON(info == NULL);
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BUG_ON(info->type != IRQT_PIRQ);
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return info->u.pirq.gsi;
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}
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static unsigned vector_from_irq(unsigned irq)
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{
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struct irq_info *info = info_for_irq(irq);
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BUG_ON(info == NULL);
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BUG_ON(info->type != IRQT_PIRQ);
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return info->u.pirq.vector;
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}
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static enum xen_irq_type type_from_irq(unsigned irq)
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{
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return info_for_irq(irq)->type;
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}
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static unsigned cpu_from_irq(unsigned irq)
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{
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return info_for_irq(irq)->cpu;
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}
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static unsigned int cpu_from_evtchn(unsigned int evtchn)
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{
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int irq = evtchn_to_irq[evtchn];
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unsigned ret = 0;
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if (irq != -1)
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ret = cpu_from_irq(irq);
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return ret;
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}
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static inline unsigned long active_evtchns(unsigned int cpu,
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struct shared_info *sh,
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unsigned int idx)
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{
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return (sh->evtchn_pending[idx] &
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cpu_evtchn_mask(cpu)[idx] &
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~sh->evtchn_mask[idx]);
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}
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static void bind_evtchn_to_cpu(unsigned int chn, unsigned int cpu)
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{
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int irq = evtchn_to_irq[chn];
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BUG_ON(irq == -1);
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#ifdef CONFIG_SMP
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cpumask_copy(irq_to_desc(irq)->affinity, cpumask_of(cpu));
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#endif
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__clear_bit(chn, cpu_evtchn_mask(cpu_from_irq(irq)));
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__set_bit(chn, cpu_evtchn_mask(cpu));
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irq_info[irq].cpu = cpu;
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}
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static void init_evtchn_cpu_bindings(void)
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{
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#ifdef CONFIG_SMP
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struct irq_desc *desc;
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int i;
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/* By default all event channels notify CPU#0. */
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for_each_irq_desc(i, desc) {
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cpumask_copy(desc->affinity, cpumask_of(0));
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}
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#endif
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memset(cpu_evtchn_mask(0), ~0, sizeof(cpu_evtchn_mask(0)));
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}
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static inline void clear_evtchn(int port)
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{
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struct shared_info *s = HYPERVISOR_shared_info;
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sync_clear_bit(port, &s->evtchn_pending[0]);
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}
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static inline void set_evtchn(int port)
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{
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struct shared_info *s = HYPERVISOR_shared_info;
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sync_set_bit(port, &s->evtchn_pending[0]);
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}
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static inline int test_evtchn(int port)
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{
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struct shared_info *s = HYPERVISOR_shared_info;
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return sync_test_bit(port, &s->evtchn_pending[0]);
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}
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/**
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* notify_remote_via_irq - send event to remote end of event channel via irq
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* @irq: irq of event channel to send event to
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*
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* Unlike notify_remote_via_evtchn(), this is safe to use across
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* save/restore. Notifications on a broken connection are silently
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* dropped.
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*/
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void notify_remote_via_irq(int irq)
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{
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int evtchn = evtchn_from_irq(irq);
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if (VALID_EVTCHN(evtchn))
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notify_remote_via_evtchn(evtchn);
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}
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EXPORT_SYMBOL_GPL(notify_remote_via_irq);
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static void mask_evtchn(int port)
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{
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struct shared_info *s = HYPERVISOR_shared_info;
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sync_set_bit(port, &s->evtchn_mask[0]);
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}
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static void unmask_evtchn(int port)
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{
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struct shared_info *s = HYPERVISOR_shared_info;
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unsigned int cpu = get_cpu();
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BUG_ON(!irqs_disabled());
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/* Slow path (hypercall) if this is a non-local port. */
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if (unlikely(cpu != cpu_from_evtchn(port))) {
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struct evtchn_unmask unmask = { .port = port };
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(void)HYPERVISOR_event_channel_op(EVTCHNOP_unmask, &unmask);
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} else {
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struct vcpu_info *vcpu_info = __get_cpu_var(xen_vcpu);
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sync_clear_bit(port, &s->evtchn_mask[0]);
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/*
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* The following is basically the equivalent of
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* 'hw_resend_irq'. Just like a real IO-APIC we 'lose
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* the interrupt edge' if the channel is masked.
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*/
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if (sync_test_bit(port, &s->evtchn_pending[0]) &&
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!sync_test_and_set_bit(port / BITS_PER_LONG,
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&vcpu_info->evtchn_pending_sel))
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vcpu_info->evtchn_upcall_pending = 1;
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}
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put_cpu();
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}
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static int find_unbound_irq(void)
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{
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int irq;
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struct irq_desc *desc;
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for (irq = 0; irq < nr_irqs; irq++)
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if (irq_info[irq].type == IRQT_UNBOUND)
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break;
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if (irq == nr_irqs)
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panic("No available IRQ to bind to: increase nr_irqs!\n");
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desc = irq_to_desc_alloc_node(irq, 0);
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if (WARN_ON(desc == NULL))
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return -1;
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dynamic_irq_init(irq);
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return irq;
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}
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int bind_evtchn_to_irq(unsigned int evtchn)
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{
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int irq;
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spin_lock(&irq_mapping_update_lock);
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irq = evtchn_to_irq[evtchn];
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if (irq == -1) {
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irq = find_unbound_irq();
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set_irq_chip_and_handler_name(irq, &xen_dynamic_chip,
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handle_level_irq, "event");
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evtchn_to_irq[evtchn] = irq;
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irq_info[irq] = mk_evtchn_info(evtchn);
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}
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spin_unlock(&irq_mapping_update_lock);
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return irq;
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}
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EXPORT_SYMBOL_GPL(bind_evtchn_to_irq);
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static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu)
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{
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struct evtchn_bind_ipi bind_ipi;
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int evtchn, irq;
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spin_lock(&irq_mapping_update_lock);
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irq = per_cpu(ipi_to_irq, cpu)[ipi];
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if (irq == -1) {
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irq = find_unbound_irq();
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if (irq < 0)
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goto out;
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set_irq_chip_and_handler_name(irq, &xen_dynamic_chip,
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handle_level_irq, "ipi");
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bind_ipi.vcpu = cpu;
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if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi,
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&bind_ipi) != 0)
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BUG();
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evtchn = bind_ipi.port;
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evtchn_to_irq[evtchn] = irq;
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irq_info[irq] = mk_ipi_info(evtchn, ipi);
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per_cpu(ipi_to_irq, cpu)[ipi] = irq;
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bind_evtchn_to_cpu(evtchn, cpu);
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}
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out:
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spin_unlock(&irq_mapping_update_lock);
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return irq;
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}
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static int bind_virq_to_irq(unsigned int virq, unsigned int cpu)
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{
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struct evtchn_bind_virq bind_virq;
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int evtchn, irq;
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spin_lock(&irq_mapping_update_lock);
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irq = per_cpu(virq_to_irq, cpu)[virq];
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if (irq == -1) {
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bind_virq.virq = virq;
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bind_virq.vcpu = cpu;
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if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq,
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&bind_virq) != 0)
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BUG();
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evtchn = bind_virq.port;
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irq = find_unbound_irq();
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set_irq_chip_and_handler_name(irq, &xen_dynamic_chip,
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handle_level_irq, "virq");
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evtchn_to_irq[evtchn] = irq;
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irq_info[irq] = mk_virq_info(evtchn, virq);
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per_cpu(virq_to_irq, cpu)[virq] = irq;
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bind_evtchn_to_cpu(evtchn, cpu);
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}
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spin_unlock(&irq_mapping_update_lock);
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return irq;
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}
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|
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static void unbind_from_irq(unsigned int irq)
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{
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struct evtchn_close close;
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int evtchn = evtchn_from_irq(irq);
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|
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spin_lock(&irq_mapping_update_lock);
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|
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if (VALID_EVTCHN(evtchn)) {
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close.port = evtchn;
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if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0)
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BUG();
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|
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switch (type_from_irq(irq)) {
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case IRQT_VIRQ:
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per_cpu(virq_to_irq, cpu_from_evtchn(evtchn))
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[virq_from_irq(irq)] = -1;
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break;
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case IRQT_IPI:
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per_cpu(ipi_to_irq, cpu_from_evtchn(evtchn))
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[ipi_from_irq(irq)] = -1;
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break;
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default:
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break;
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}
|
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|
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/* Closed ports are implicitly re-bound to VCPU0. */
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bind_evtchn_to_cpu(evtchn, 0);
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|
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evtchn_to_irq[evtchn] = -1;
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}
|
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|
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if (irq_info[irq].type != IRQT_UNBOUND) {
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irq_info[irq] = mk_unbound_info();
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|
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dynamic_irq_cleanup(irq);
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}
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|
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spin_unlock(&irq_mapping_update_lock);
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}
|
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|
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int bind_evtchn_to_irqhandler(unsigned int evtchn,
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irq_handler_t handler,
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unsigned long irqflags,
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const char *devname, void *dev_id)
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{
|
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unsigned int irq;
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int retval;
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|
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irq = bind_evtchn_to_irq(evtchn);
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retval = request_irq(irq, handler, irqflags, devname, dev_id);
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if (retval != 0) {
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unbind_from_irq(irq);
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return retval;
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}
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|
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return irq;
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}
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EXPORT_SYMBOL_GPL(bind_evtchn_to_irqhandler);
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|
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int bind_virq_to_irqhandler(unsigned int virq, unsigned int cpu,
|
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irq_handler_t handler,
|
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unsigned long irqflags, const char *devname, void *dev_id)
|
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{
|
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unsigned int irq;
|
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int retval;
|
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|
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irq = bind_virq_to_irq(virq, cpu);
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retval = request_irq(irq, handler, irqflags, devname, dev_id);
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if (retval != 0) {
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unbind_from_irq(irq);
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return retval;
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}
|
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|
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return irq;
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}
|
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EXPORT_SYMBOL_GPL(bind_virq_to_irqhandler);
|
|
|
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int bind_ipi_to_irqhandler(enum ipi_vector ipi,
|
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unsigned int cpu,
|
|
irq_handler_t handler,
|
|
unsigned long irqflags,
|
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const char *devname,
|
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void *dev_id)
|
|
{
|
|
int irq, retval;
|
|
|
|
irq = bind_ipi_to_irq(ipi, cpu);
|
|
if (irq < 0)
|
|
return irq;
|
|
|
|
retval = request_irq(irq, handler, irqflags, devname, dev_id);
|
|
if (retval != 0) {
|
|
unbind_from_irq(irq);
|
|
return retval;
|
|
}
|
|
|
|
return irq;
|
|
}
|
|
|
|
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);
|
|
|
|
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);
|
|
}
|
|
|
|
irqreturn_t xen_debug_interrupt(int irq, void *dev_id)
|
|
{
|
|
struct shared_info *sh = HYPERVISOR_shared_info;
|
|
int cpu = smp_processor_id();
|
|
int i;
|
|
unsigned long flags;
|
|
static DEFINE_SPINLOCK(debug_lock);
|
|
|
|
spin_lock_irqsave(&debug_lock, flags);
|
|
|
|
printk("vcpu %d\n ", cpu);
|
|
|
|
for_each_online_cpu(i) {
|
|
struct vcpu_info *v = per_cpu(xen_vcpu, i);
|
|
printk("%d: masked=%d pending=%d event_sel %08lx\n ", i,
|
|
(get_irq_regs() && i == cpu) ? xen_irqs_disabled(get_irq_regs()) : v->evtchn_upcall_mask,
|
|
v->evtchn_upcall_pending,
|
|
v->evtchn_pending_sel);
|
|
}
|
|
printk("pending:\n ");
|
|
for(i = ARRAY_SIZE(sh->evtchn_pending)-1; i >= 0; i--)
|
|
printk("%08lx%s", sh->evtchn_pending[i],
|
|
i % 8 == 0 ? "\n " : " ");
|
|
printk("\nmasks:\n ");
|
|
for(i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--)
|
|
printk("%08lx%s", sh->evtchn_mask[i],
|
|
i % 8 == 0 ? "\n " : " ");
|
|
|
|
printk("\nunmasked:\n ");
|
|
for(i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--)
|
|
printk("%08lx%s", sh->evtchn_pending[i] & ~sh->evtchn_mask[i],
|
|
i % 8 == 0 ? "\n " : " ");
|
|
|
|
printk("\npending list:\n");
|
|
for(i = 0; i < NR_EVENT_CHANNELS; i++) {
|
|
if (sync_test_bit(i, sh->evtchn_pending)) {
|
|
printk(" %d: event %d -> irq %d\n",
|
|
cpu_from_evtchn(i), i,
|
|
evtchn_to_irq[i]);
|
|
}
|
|
}
|
|
|
|
spin_unlock_irqrestore(&debug_lock, flags);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static DEFINE_PER_CPU(unsigned, xed_nesting_count);
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
void xen_evtchn_do_upcall(struct pt_regs *regs)
|
|
{
|
|
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;
|
|
|
|
vcpu_info->evtchn_upcall_pending = 0;
|
|
|
|
if (__get_cpu_var(xed_nesting_count)++)
|
|
goto out;
|
|
|
|
#ifndef CONFIG_X86 /* No need for a barrier -- XCHG is a barrier on x86. */
|
|
/* Clear master flag /before/ clearing selector flag. */
|
|
wmb();
|
|
#endif
|
|
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];
|
|
|
|
if (irq != -1)
|
|
handle_irq(irq, regs);
|
|
}
|
|
}
|
|
|
|
BUG_ON(!irqs_disabled());
|
|
|
|
count = __get_cpu_var(xed_nesting_count);
|
|
__get_cpu_var(xed_nesting_count) = 0;
|
|
} while(count != 1);
|
|
|
|
out:
|
|
irq_exit();
|
|
set_irq_regs(old_regs);
|
|
|
|
put_cpu();
|
|
}
|
|
|
|
/* Rebind a new event channel to an existing irq. */
|
|
void rebind_evtchn_irq(int evtchn, int irq)
|
|
{
|
|
struct irq_info *info = info_for_irq(irq);
|
|
|
|
/* 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,
|
|
so there should be a proper type */
|
|
BUG_ON(info->type == IRQT_UNBOUND);
|
|
|
|
evtchn_to_irq[evtchn] = irq;
|
|
irq_info[irq] = mk_evtchn_info(evtchn);
|
|
|
|
spin_unlock(&irq_mapping_update_lock);
|
|
|
|
/* new event channels are always bound to cpu 0 */
|
|
irq_set_affinity(irq, cpumask_of(0));
|
|
|
|
/* Unmask the event channel. */
|
|
enable_irq(irq);
|
|
}
|
|
|
|
/* Rebind an evtchn so that it gets delivered to a specific cpu */
|
|
static int rebind_irq_to_cpu(unsigned irq, unsigned tcpu)
|
|
{
|
|
struct evtchn_bind_vcpu bind_vcpu;
|
|
int evtchn = evtchn_from_irq(irq);
|
|
|
|
if (!VALID_EVTCHN(evtchn))
|
|
return -1;
|
|
|
|
/* 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);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int set_affinity_irq(unsigned irq, const struct cpumask *dest)
|
|
{
|
|
unsigned tcpu = cpumask_first(dest);
|
|
|
|
return rebind_irq_to_cpu(irq, tcpu);
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
static void enable_dynirq(unsigned int irq)
|
|
{
|
|
int evtchn = evtchn_from_irq(irq);
|
|
|
|
if (VALID_EVTCHN(evtchn))
|
|
unmask_evtchn(evtchn);
|
|
}
|
|
|
|
static void disable_dynirq(unsigned int irq)
|
|
{
|
|
int evtchn = evtchn_from_irq(irq);
|
|
|
|
if (VALID_EVTCHN(evtchn))
|
|
mask_evtchn(evtchn);
|
|
}
|
|
|
|
static void ack_dynirq(unsigned int irq)
|
|
{
|
|
int evtchn = evtchn_from_irq(irq);
|
|
|
|
move_native_irq(irq);
|
|
|
|
if (VALID_EVTCHN(evtchn))
|
|
clear_evtchn(evtchn);
|
|
}
|
|
|
|
static int retrigger_dynirq(unsigned int irq)
|
|
{
|
|
int evtchn = evtchn_from_irq(irq);
|
|
struct shared_info *sh = HYPERVISOR_shared_info;
|
|
int ret = 0;
|
|
|
|
if (VALID_EVTCHN(evtchn)) {
|
|
int masked;
|
|
|
|
masked = sync_test_and_set_bit(evtchn, sh->evtchn_mask);
|
|
sync_set_bit(evtchn, sh->evtchn_pending);
|
|
if (!masked)
|
|
unmask_evtchn(evtchn);
|
|
ret = 1;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
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;
|
|
|
|
BUG_ON(virq_from_irq(irq) != virq);
|
|
|
|
/* 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. */
|
|
evtchn_to_irq[evtchn] = irq;
|
|
irq_info[irq] = mk_virq_info(evtchn, virq);
|
|
bind_evtchn_to_cpu(evtchn, cpu);
|
|
|
|
/* Ready for use. */
|
|
unmask_evtchn(evtchn);
|
|
}
|
|
}
|
|
|
|
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;
|
|
|
|
BUG_ON(ipi_from_irq(irq) != ipi);
|
|
|
|
/* 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. */
|
|
evtchn_to_irq[evtchn] = irq;
|
|
irq_info[irq] = mk_ipi_info(evtchn, ipi);
|
|
bind_evtchn_to_cpu(evtchn, cpu);
|
|
|
|
/* Ready for use. */
|
|
unmask_evtchn(evtchn);
|
|
|
|
}
|
|
}
|
|
|
|
/* 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);
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
/* 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)
|
|
{
|
|
evtchn_port_t evtchn = evtchn_from_irq(irq);
|
|
|
|
if (VALID_EVTCHN(evtchn)) {
|
|
struct sched_poll poll;
|
|
|
|
poll.nr_ports = 1;
|
|
poll.timeout = 0;
|
|
set_xen_guest_handle(poll.ports, &evtchn);
|
|
|
|
if (HYPERVISOR_sched_op(SCHEDOP_poll, &poll) != 0)
|
|
BUG();
|
|
}
|
|
}
|
|
|
|
void xen_irq_resume(void)
|
|
{
|
|
unsigned int cpu, irq, evtchn;
|
|
|
|
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. */
|
|
for (irq = 0; irq < nr_irqs; irq++)
|
|
irq_info[irq].evtchn = 0; /* zap event-channel binding */
|
|
|
|
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);
|
|
}
|
|
}
|
|
|
|
static struct irq_chip xen_dynamic_chip __read_mostly = {
|
|
.name = "xen-dyn",
|
|
|
|
.disable = disable_dynirq,
|
|
.mask = disable_dynirq,
|
|
.unmask = enable_dynirq,
|
|
|
|
.ack = ack_dynirq,
|
|
.set_affinity = set_affinity_irq,
|
|
.retrigger = retrigger_dynirq,
|
|
};
|
|
|
|
void __init xen_init_IRQ(void)
|
|
{
|
|
int i;
|
|
|
|
cpu_evtchn_mask_p = kcalloc(nr_cpu_ids, sizeof(struct cpu_evtchn_s),
|
|
GFP_KERNEL);
|
|
BUG_ON(cpu_evtchn_mask_p == NULL);
|
|
|
|
init_evtchn_cpu_bindings();
|
|
|
|
/* No event channels are 'live' right now. */
|
|
for (i = 0; i < NR_EVENT_CHANNELS; i++)
|
|
mask_evtchn(i);
|
|
|
|
irq_ctx_init(smp_processor_id());
|
|
}
|