Xen: make events.c portable for ia64/xen support

Remove x86 dependency in drivers/xen/events.c for ia64/xen support
introducing include/asm/xen/events.h.
Introduce xen_irqs_disabled() to hide regs->flags
Introduce xen_do_IRQ() to hide regs->orig_ax.
make enum ipi_vector definition arch specific. ia64/xen needs four vectors.
Add one rmb() because on ia64 xchg() isn't barrier.

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>

1 files changed, 7 insertions, 6 deletions

diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index c50d499b1e6f..2396b4492f70 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -469,7 +469,7 @@ irqreturn_t xen_debug_interrupt(int irq, void *dev_id)
         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,
+                        (get_irq_regs() && i == cpu) ? xen_irqs_disabled(get_irq_regs()) : v->evtchn_upcall_mask,
                         v->evtchn_upcall_pending,
                         v->evtchn_pending_sel);
         }
@@ -527,7 +527,10 @@ void xen_evtchn_do_upcall(struct pt_regs *regs)
                 if (__get_cpu_var(nesting_count)++)
                         goto out;
 
-                /* NB. No need for a barrier here -- XCHG is a barrier on x86. */
+#ifndef CONFIG_X86 /* No need for a barrier -- XCHG is a barrier on x86. */
+                /* Clear master flag /before/ clearing selector flag. */
+                rmb();
+#endif
                 pending_words = xchg(&vcpu_info->evtchn_pending_sel, 0);
                 while (pending_words != 0) {
                         unsigned long pending_bits;
@@ -539,10 +542,8 @@ void xen_evtchn_do_upcall(struct pt_regs *regs)
                                 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);
-                                }
+                                if (irq != -1)
+                                        xen_do_IRQ(irq, regs);
                         }
                 }