[RFC PATCH V2 08/14] Define N-level event channel registration interface

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

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
---
 xen/include/public/event_channel.h |   33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/xen/include/public/event_channel.h b/xen/include/public/event_channel.h
index 07ff321..c5194d9 100644
--- a/xen/include/public/event_channel.h
+++ b/xen/include/public/event_channel.h
@@ -71,6 +71,7 @@
 #define EVTCHNOP_bind_vcpu        8
 #define EVTCHNOP_unmask           9
 #define EVTCHNOP_reset           10
+#define EVTCHNOP_register_nlevel 11
 /* ` } */
 
 typedef uint32_t evtchn_port_t;
@@ -258,6 +259,38 @@ struct evtchn_reset {
 typedef struct evtchn_reset evtchn_reset_t;
 
 /*
+ * EVTCHNOP_register_nlevel: Register N-level event channel
+ * NOTES:
+ *  1. Currently only 3-level is supported.
+ *  2. Should fall back to 2-level if this call fails.
+ */
+/* 64 bit guests need 8 pages for evtchn_pending and evtchn_mask for
+ * 256k event channels while 32 bit ones only need 1 page for 32k
+ * event channels. */
+#define EVTCHN_MAX_L3_PAGES 8
+struct evtchn_register_3level {
+    /* IN parameters. */
+    uint32_t nr_pages;
+    XEN_GUEST_HANDLE(xen_pfn_t) evtchn_pending;
+    XEN_GUEST_HANDLE(xen_pfn_t) evtchn_mask;
+    uint32_t nr_vcpus;
+    XEN_GUEST_HANDLE(xen_pfn_t) l2sel_mfns;
+    XEN_GUEST_HANDLE(xen_pfn_t) l2sel_offsets;
+};
+typedef struct evtchn_register_3level evtchn_register_3level_t;
+DEFINE_XEN_GUEST_HANDLE(evtchn_register_3level_t);
+
+struct evtchn_register_nlevel {
+    /* IN parameters. */
+    uint32_t level;
+    union {
+        XEN_GUEST_HANDLE(evtchn_register_3level_t) l3;
+    } u;
+};
+typedef struct evtchn_register_nlevel evtchn_register_nlevel_t;
+DEFINE_XEN_GUEST_HANDLE(evtchn_register_nlevel_t);
+
+/*
  * ` enum neg_errnoval
  * ` HYPERVISOR_event_channel_op_compat(struct evtchn_op *op)
  * `
-- 
1.7.10.4