[RFC PATCH V2 6/8] xen: introduce xen_event_channel_register_3level

[Wei Liu <wei.liu2@citrix.com>]

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
---
 drivers/xen/events.c |   71 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 71 insertions(+)

diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index 5b45441..cbb10ed 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -2178,6 +2178,77 @@ static struct evtchn_ops evtchn_ops_l3 __read_mostly = {
 	.debug_interrupt   = debug_interrupt_l3,
 };
 
+static int xen_event_channel_register_3level(void)
+{
+	evtchn_register_nlevel_t reg;
+	evtchn_register_3level_t l3;
+	int i, nr_pages, cpu;
+	unsigned long *_evtchn_pending = NULL;
+	unsigned long *_evtchn_mask = NULL;
+	unsigned long *l2sel_mfns = NULL;
+	unsigned long *l2sel_offsets = NULL;
+	int rc;
+
+	/* 1 page for 32 bit and 8 pages for 64 bit */
+	nr_pages = (sizeof(unsigned long) == 4 ? 1 : 8);
+
+	rc = -ENOMEM;
+#define __ALLOC_ARRAY(_ptr, _nr)					\
+	do {								\
+		(_ptr) = kzalloc(sizeof(unsigned long) * (_nr),		\
+				 GFP_KERNEL);				\
+		if (!(_ptr))						\
+			goto out;					\
+	} while (0)
+
+	__ALLOC_ARRAY(_evtchn_pending, nr_pages);
+	__ALLOC_ARRAY(_evtchn_mask, nr_pages);
+	__ALLOC_ARRAY(l2sel_mfns, nr_cpu_ids);
+	__ALLOC_ARRAY(l2sel_offsets, nr_cpu_ids);
+#undef __ALLOC_ARRAY
+
+	memset(&reg, 0, sizeof(reg));
+	memset(&l3,  0, sizeof(l3));
+
+	for (i = 0; i < nr_pages; i++) {
+		unsigned long offset = PAGE_SIZE * i;
+		_evtchn_pending[i] =
+			arbitrary_virt_to_mfn(
+				(void *)((unsigned long)evtchn_pending+offset));
+		_evtchn_mask[i] =
+			arbitrary_virt_to_mfn(
+				(void *)((unsigned long)evtchn_mask+offset));
+	}
+
+	for_each_possible_cpu(cpu) {
+		l2sel_mfns[cpu] =
+			arbitrary_virt_to_mfn(&per_cpu(evtchn_sel_l2, cpu));
+		l2sel_offsets[cpu] =
+			offset_in_page(&per_cpu(evtchn_sel_l2, cpu));
+	}
+
+	l3.nr_pages = nr_pages;
+	l3.evtchn_pending = _evtchn_pending;
+	l3.evtchn_mask = _evtchn_mask;
+
+	l3.nr_vcpus = nr_cpu_ids;
+	l3.l2sel_mfns = l2sel_mfns;
+	l3.l2sel_offsets = l2sel_offsets;
+
+	reg.level = 3;
+	reg.u.l3  = &l3;
+
+	rc = HYPERVISOR_event_channel_op(EVTCHNOP_register_nlevel, &reg);
+
+out:
+	kfree(_evtchn_pending);
+	kfree(_evtchn_mask);
+	kfree(l2sel_mfns);
+	kfree(l2sel_offsets);
+
+	return rc;
+}
+
 void __init xen_init_IRQ(void)
 {
 	int i, rc;
-- 
1.7.10.4