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-rw-r--r--arch/i386/xen/events.c591
1 files changed, 0 insertions, 591 deletions
diff --git a/arch/i386/xen/events.c b/arch/i386/xen/events.c
deleted file mode 100644
index da1b173..0000000
--- a/arch/i386/xen/events.c
+++ /dev/null
@@ -1,591 +0,0 @@
-/*
- * 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.
- * 4. Hardware interrupts. Not supported at present.
- *
- * 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>
-
-#include <asm/ptrace.h>
-#include <asm/irq.h>
-#include <asm/sync_bitops.h>
-#include <asm/xen/hypercall.h>
-#include <asm/xen/hypervisor.h>
-
-#include <xen/events.h>
-#include <xen/interface/xen.h>
-#include <xen/interface/event_channel.h>
-
-#include "xen-ops.h"
-
-/*
- * 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);
-
-/* IRQ <-> VIRQ mapping. */
-static DEFINE_PER_CPU(int, virq_to_irq[NR_VIRQS]) = {[0 ... NR_VIRQS-1] = -1};
-
-/* IRQ <-> IPI mapping */
-static DEFINE_PER_CPU(int, ipi_to_irq[XEN_NR_IPIS]) = {[0 ... XEN_NR_IPIS-1] = -1};
-
-/* Packed IRQ information: binding type, sub-type index, and event channel. */
-struct packed_irq
-{
- unsigned short evtchn;
- unsigned char index;
- unsigned char type;
-};
-
-static struct packed_irq irq_info[NR_IRQS];
-
-/* Binding types. */
-enum {
- IRQT_UNBOUND,
- IRQT_PIRQ,
- IRQT_VIRQ,
- IRQT_IPI,
- IRQT_EVTCHN
-};
-
-/* Convenient shorthand for packed representation of an unbound IRQ. */
-#define IRQ_UNBOUND mk_irq_info(IRQT_UNBOUND, 0, 0)
-
-static int evtchn_to_irq[NR_EVENT_CHANNELS] = {
- [0 ... NR_EVENT_CHANNELS-1] = -1
-};
-static unsigned long cpu_evtchn_mask[NR_CPUS][NR_EVENT_CHANNELS/BITS_PER_LONG];
-static u8 cpu_evtchn[NR_EVENT_CHANNELS];
-
-/* Reference counts for bindings to IRQs. */
-static int irq_bindcount[NR_IRQS];
-
-/* Xen will never allocate port zero for any purpose. */
-#define VALID_EVTCHN(chn) ((chn) != 0)
-
-/*
- * Force a proper event-channel callback from Xen after clearing the
- * callback mask. We do this in a very simple manner, by making a call
- * down into Xen. The pending flag will be checked by Xen on return.
- */
-void force_evtchn_callback(void)
-{
- (void)HYPERVISOR_xen_version(0, NULL);
-}
-EXPORT_SYMBOL_GPL(force_evtchn_callback);
-
-static struct irq_chip xen_dynamic_chip;
-
-/* Constructor for packed IRQ information. */
-static inline struct packed_irq mk_irq_info(u32 type, u32 index, u32 evtchn)
-{
- return (struct packed_irq) { evtchn, index, type };
-}
-
-/*
- * Accessors for packed IRQ information.
- */
-static inline unsigned int evtchn_from_irq(int irq)
-{
- return irq_info[irq].evtchn;
-}
-
-static inline unsigned int index_from_irq(int irq)
-{
- return irq_info[irq].index;
-}
-
-static inline unsigned int type_from_irq(int irq)
-{
- return irq_info[irq].type;
-}
-
-static inline unsigned long active_evtchns(unsigned int cpu,
- struct shared_info *sh,
- unsigned int idx)
-{
- return (sh->evtchn_pending[idx] &
- cpu_evtchn_mask[cpu][idx] &
- ~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
- irq_desc[irq].affinity = cpumask_of_cpu(cpu);
-#endif
-
- __clear_bit(chn, cpu_evtchn_mask[cpu_evtchn[chn]]);
- __set_bit(chn, cpu_evtchn_mask[cpu]);
-
- cpu_evtchn[chn] = cpu;
-}
-
-static void init_evtchn_cpu_bindings(void)
-{
-#ifdef CONFIG_SMP
- int i;
- /* By default all event channels notify CPU#0. */
- for (i = 0; i < NR_IRQS; i++)
- irq_desc[i].affinity = cpumask_of_cpu(0);
-#endif
-
- memset(cpu_evtchn, 0, sizeof(cpu_evtchn));
- memset(cpu_evtchn_mask[0], ~0, sizeof(cpu_evtchn_mask[0]));
-}
-
-static inline unsigned int cpu_from_evtchn(unsigned int evtchn)
-{
- return cpu_evtchn[evtchn];
-}
-
-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]);
-}
-
-
-/**
- * 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 {
- struct vcpu_info *vcpu_info = __get_cpu_var(xen_vcpu);
-
- 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();
-}
-
-static int find_unbound_irq(void)
-{
- int irq;
-
- /* Only allocate from dynirq range */
- for (irq = 0; irq < NR_IRQS; irq++)
- if (irq_bindcount[irq] == 0)
- break;
-
- if (irq == NR_IRQS)
- panic("No available IRQ to bind to: increase NR_IRQS!\n");
-
- return irq;
-}
-
-int bind_evtchn_to_irq(unsigned int evtchn)
-{
- int irq;
-
- spin_lock(&irq_mapping_update_lock);
-
- irq = evtchn_to_irq[evtchn];
-
- if (irq == -1) {
- irq = find_unbound_irq();
-
- dynamic_irq_init(irq);
- set_irq_chip_and_handler_name(irq, &xen_dynamic_chip,
- handle_level_irq, "event");
-
- evtchn_to_irq[evtchn] = irq;
- irq_info[irq] = mk_irq_info(IRQT_EVTCHN, 0, evtchn);
- }
-
- irq_bindcount[irq]++;
-
- spin_unlock(&irq_mapping_update_lock);
-
- return irq;
-}
-EXPORT_SYMBOL_GPL(bind_evtchn_to_irq);
-
-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];
- if (irq == -1) {
- irq = find_unbound_irq();
- if (irq < 0)
- goto out;
-
- dynamic_irq_init(irq);
- set_irq_chip_and_handler_name(irq, &xen_dynamic_chip,
- handle_level_irq, "ipi");
-
- bind_ipi.vcpu = cpu;
- if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi,
- &bind_ipi) != 0)
- BUG();
- evtchn = bind_ipi.port;
-
- evtchn_to_irq[evtchn] = irq;
- irq_info[irq] = mk_irq_info(IRQT_IPI, ipi, evtchn);
-
- per_cpu(ipi_to_irq, cpu)[ipi] = irq;
-
- bind_evtchn_to_cpu(evtchn, cpu);
- }
-
- irq_bindcount[irq]++;
-
- out:
- spin_unlock(&irq_mapping_update_lock);
- return irq;
-}
-
-
-static int bind_virq_to_irq(unsigned int virq, unsigned int cpu)
-{
- 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) {
- bind_virq.virq = virq;
- bind_virq.vcpu = cpu;
- if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq,
- &bind_virq) != 0)
- BUG();
- evtchn = bind_virq.port;
-
- irq = find_unbound_irq();
-
- dynamic_irq_init(irq);
- set_irq_chip_and_handler_name(irq, &xen_dynamic_chip,
- handle_level_irq, "virq");
-
- evtchn_to_irq[evtchn] = irq;
- irq_info[irq] = mk_irq_info(IRQT_VIRQ, virq, evtchn);
-
- per_cpu(virq_to_irq, cpu)[virq] = irq;
-
- bind_evtchn_to_cpu(evtchn, cpu);
- }
-
- irq_bindcount[irq]++;
-
- 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);
-
- if (VALID_EVTCHN(evtchn) && (--irq_bindcount[irq] == 0)) {
- 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))
- [index_from_irq(irq)] = -1;
- break;
- default:
- break;
- }
-
- /* Closed ports are implicitly re-bound to VCPU0. */
- bind_evtchn_to_cpu(evtchn, 0);
-
- evtchn_to_irq[evtchn] = -1;
- irq_info[irq] = IRQ_UNBOUND;
-
- dynamic_irq_init(irq);
- }
-
- spin_unlock(&irq_mapping_update_lock);
-}
-
-int bind_evtchn_to_irqhandler(unsigned int evtchn,
- irqreturn_t (*handler)(int, void *),
- 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,
- irqreturn_t (*handler)(int, void *),
- 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);
-
-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;
-
- 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);
-}
-
-
-/*
- * 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.
- */
-fastcall void xen_evtchn_do_upcall(struct pt_regs *regs)
-{
- int cpu = get_cpu();
- struct shared_info *s = HYPERVISOR_shared_info;
- struct vcpu_info *vcpu_info = __get_cpu_var(xen_vcpu);
- unsigned long pending_words;
-
- vcpu_info->evtchn_upcall_pending = 0;
-
- /* NB. No need for a barrier here -- XCHG is a barrier on x86. */
- 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) {
- regs->orig_eax = ~irq;
- do_IRQ(regs);
- }
- }
- }
-
- put_cpu();
-}
-
-/* Rebind an evtchn so that it gets delivered to a specific cpu */
-static void 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;
-
- /* 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);
-}
-
-
-static void set_affinity_irq(unsigned irq, cpumask_t dest)
-{
- unsigned tcpu = first_cpu(dest);
- rebind_irq_to_cpu(irq, tcpu);
-}
-
-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);
- int ret = 0;
-
- if (VALID_EVTCHN(evtchn)) {
- set_evtchn(evtchn);
- ret = 1;
- }
-
- return ret;
-}
-
-static struct irq_chip xen_dynamic_chip __read_mostly = {
- .name = "xen-dyn",
- .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;
-
- init_evtchn_cpu_bindings();
-
- /* No event channels are 'live' right now. */
- for (i = 0; i < NR_EVENT_CHANNELS; i++)
- mask_evtchn(i);
-
- /* Dynamic IRQ space is currently unbound. Zero the refcnts. */
- for (i = 0; i < NR_IRQS; i++)
- irq_bindcount[i] = 0;
-
- irq_ctx_init(smp_processor_id());
-}
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