xen: move events.c to drivers/xen for IA64/Xen support

move arch/x86/xen/events.c undedr drivers/xen to share codes
with x86 and ia64. And minor adjustment to compile.
ia64/xen also uses events.c

Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@intel.com>
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

3 files changed, 2 insertions, 660 deletions

diff --git a/arch/x86/xen/Makefile b/arch/x86/xen/Makefile
index c5e9aa48990..95c59260dcc 100644
--- a/arch/x86/xen/Makefile
+++ b/arch/x86/xen/Makefile
@@ -1,4 +1,4 @@
 obj-y		:= enlighten.o setup.o multicalls.o mmu.o \
-			events.o time.o manage.o xen-asm.o
+			time.o manage.o xen-asm.o
 
 obj-$(CONFIG_SMP)	+= smp.o
diff --git a/arch/x86/xen/events.c b/arch/x86/xen/events.c
deleted file mode 100644
index 85bac298b3c..00000000000
--- a/arch/x86/xen/events.c
+++ /dev/null
@@ -1,658 +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,
-			      irq_handler_t handler,
-			      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,
-			    irq_handler_t handler,
-			    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);
-}
-
-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) ? !(get_irq_regs()->flags & X86_EFLAGS_IF) : 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_evtchn[i], i,
-				evtchn_to_irq[i]);
-		}
-	}
-
-	spin_unlock_irqrestore(&debug_lock, flags);
-
-	return IRQ_HANDLED;
-}
-
-
-/*
- * 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 shared_info *s = HYPERVISOR_shared_info;
-	struct vcpu_info *vcpu_info = __get_cpu_var(xen_vcpu);
-	static DEFINE_PER_CPU(unsigned, nesting_count);
- 	unsigned count;
-
-	do {
-		unsigned long pending_words;
-
-		vcpu_info->evtchn_upcall_pending = 0;
-
-		if (__get_cpu_var(nesting_count)++)
-			goto out;
-
-		/* 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_ax = ~irq;
-					do_IRQ(regs);
-				}
-			}
-		}
-
-		BUG_ON(!irqs_disabled());
-
-		count = __get_cpu_var(nesting_count);
-		__get_cpu_var(nesting_count) = 0;
-	} while(count != 1);
-
-out:
-	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);
-	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 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());
-}
diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h
index 22395d20dd6..f1063ae0803 100644
--- a/arch/x86/xen/xen-ops.h
+++ b/arch/x86/xen/xen-ops.h
@@ -3,6 +3,7 @@
 
 #include <linux/init.h>
 #include <linux/irqreturn.h>
+#include <xen/xen-ops.h>
 
 /* These are code, but not functions.  Defined in entry.S */
 extern const char xen_hypervisor_callback[];
@@ -10,7 +11,6 @@ extern const char xen_failsafe_callback[];
 
 void xen_copy_trap_info(struct trap_info *traps);
 
-DECLARE_PER_CPU(struct vcpu_info *, xen_vcpu);
 DECLARE_PER_CPU(unsigned long, xen_cr3);
 DECLARE_PER_CPU(unsigned long, xen_current_cr3);