X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Fx86_64%2Fkernel%2Firqflags-xen.c;fp=arch%2Fx86_64%2Fkernel%2Firqflags-xen.c;h=e3b7ab5e6cf2e60e6540caeb4590245596957f5d;hb=f05f9504c50ed069377d37f02f22e7a16b5921de;hp=0000000000000000000000000000000000000000;hpb=16c70f8c1b54b61c3b951b6fb220df250fe09b32;p=linux-2.6.git

diff --git a/arch/x86_64/kernel/irqflags-xen.c b/arch/x86_64/kernel/irqflags-xen.c
new file mode 100644
index 000000000..e3b7ab5e6
--- /dev/null
+++ b/arch/x86_64/kernel/irqflags-xen.c
@@ -0,0 +1,100 @@
+#include <linux/module.h>
+#include <linux/smp.h>
+#include <asm/irqflags.h>
+#include <asm/hypervisor.h>
+
+/* 
+ * The use of 'barrier' in the following reflects their use as local-lock
+ * operations. Reentrancy must be prevented (e.g., __cli()) /before/ following
+ * critical operations are executed. All critical operations must complete
+ * /before/ reentrancy is permitted (e.g., __sti()). Alpha architecture also
+ * includes these barriers, for example.
+ */
+
+unsigned long __raw_local_save_flags(void)
+{
+	struct vcpu_info *_vcpu;
+	unsigned long flags;
+
+	preempt_disable();
+	_vcpu = &HYPERVISOR_shared_info->vcpu_info[__vcpu_id];
+	flags = _vcpu->evtchn_upcall_mask;
+	preempt_enable();
+
+	return flags;
+}
+EXPORT_SYMBOL(__raw_local_save_flags);
+
+void raw_local_irq_restore(unsigned long flags)
+{
+	struct vcpu_info *_vcpu;
+	preempt_disable();
+	_vcpu = &HYPERVISOR_shared_info->vcpu_info[__vcpu_id];
+	if ((_vcpu->evtchn_upcall_mask = flags) == 0) {
+		barrier(); /* unmask then check (avoid races) */
+		if ( unlikely(_vcpu->evtchn_upcall_pending) )
+			force_evtchn_callback();
+		preempt_enable();
+	} else
+		preempt_enable_no_resched();
+}
+EXPORT_SYMBOL(raw_local_irq_restore);
+
+void raw_local_irq_disable(void)
+{
+	struct vcpu_info *_vcpu;
+
+	preempt_disable();
+	_vcpu = &HYPERVISOR_shared_info->vcpu_info[__vcpu_id];
+	_vcpu->evtchn_upcall_mask = 1;
+	preempt_enable_no_resched();
+}
+EXPORT_SYMBOL(raw_local_irq_disable);
+
+void raw_local_irq_enable(void)
+{
+	struct vcpu_info *_vcpu;
+
+	preempt_disable();
+	_vcpu = &HYPERVISOR_shared_info->vcpu_info[__vcpu_id];
+	_vcpu->evtchn_upcall_mask = 0;
+	barrier(); /* unmask then check (avoid races) */
+	if ( unlikely(_vcpu->evtchn_upcall_pending) )
+		force_evtchn_callback();
+	preempt_enable();
+}
+EXPORT_SYMBOL(raw_local_irq_enable);
+
+/*
+ * For spinlocks, etc.:
+ */
+
+unsigned long __raw_local_irq_save(void)
+{
+	struct vcpu_info *_vcpu;
+	unsigned long flags;
+
+	preempt_disable();
+	_vcpu = &HYPERVISOR_shared_info->vcpu_info[__vcpu_id];
+	flags = _vcpu->evtchn_upcall_mask;
+	_vcpu->evtchn_upcall_mask = 1;
+	preempt_enable_no_resched();
+
+	return flags;
+}
+EXPORT_SYMBOL(__raw_local_irq_save);
+
+/* Cannot use preempt_enable() here as we would recurse in preempt_sched(). */
+int raw_irqs_disabled(void)
+{
+	struct vcpu_info *_vcpu;
+	int disabled;
+
+	preempt_disable();
+	_vcpu = &HYPERVISOR_shared_info->vcpu_info[__vcpu_id];
+	disabled = (_vcpu->evtchn_upcall_mask != 0);
+	preempt_enable_no_resched();
+
+	return disabled;
+}
+EXPORT_SYMBOL(raw_irqs_disabled);