[PATCH v6 04/11] libxl: ocaml: allow device operations to be called asynchronously

[Rob Hoes <rob.hoes@citrix.com>]

Signed-off-by: Rob Hoes <rob.hoes@citrix.com>
CC: David Scott <dave.scott@eu.citrix.com>
CC: Ian Campbell <ian.campbell@citrix.com>

---
v6: Updated patch to register for_callback value with the GC.
---
 tools/ocaml/libs/xl/genwrap.py       |    6 +++---
 tools/ocaml/libs/xl/xenlight_stubs.c |   18 +++++++++++++++---
 2 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/tools/ocaml/libs/xl/genwrap.py b/tools/ocaml/libs/xl/genwrap.py
index f5d2224..dd43069 100644
--- a/tools/ocaml/libs/xl/genwrap.py
+++ b/tools/ocaml/libs/xl/genwrap.py
@@ -22,9 +22,9 @@ builtins = {
     "libxl_cpuid_policy_list": ("unit",                "%(c)s = 0",                         "Val_unit"),
     }
 
-DEVICE_FUNCTIONS = [ ("add",            ["ctx", "t", "domid", "unit"]),
-                     ("remove",         ["ctx", "t", "domid", "unit"]),
-                     ("destroy",        ["ctx", "t", "domid", "unit"]),
+DEVICE_FUNCTIONS = [ ("add",            ["ctx", "t", "domid", "?async:'a", "unit", "unit"]),
+                     ("remove",         ["ctx", "t", "domid", "?async:'a", "unit", "unit"]),
+                     ("destroy",        ["ctx", "t", "domid", "?async:'a", "unit", "unit"]),
                    ]
 
 functions = { # ( name , [type1,type2,....] )
diff --git a/tools/ocaml/libs/xl/xenlight_stubs.c b/tools/ocaml/libs/xl/xenlight_stubs.c
index 660dd09..b6649a7 100644
--- a/tools/ocaml/libs/xl/xenlight_stubs.c
+++ b/tools/ocaml/libs/xl/xenlight_stubs.c
@@ -401,15 +401,27 @@ void async_callback(libxl_ctx *ctx, int rc, void *for_callback)
 #define STRINGIFY(x) _STRINGIFY(x)
 
 #define _DEVICE_ADDREMOVE(type,op)					\
-value stub_xl_device_##type##_##op(value ctx, value info, value domid)	\
+value stub_xl_device_##type##_##op(value ctx, value info, value domid,	\
+	value async, value unit)					\
 {									\
-	CAMLparam3(ctx, info, domid);					\
+	CAMLparam5(ctx, info, domid, async, unit);			\
 	libxl_device_##type c_info;					\
 	int ret, marker_var;						\
+	libxl_asyncop_how ao_how;					\
+	value *p;							\
 									\
 	device_##type##_val(CTX, &c_info, info);			\
 									\
-	ret = libxl_device_##type##_##op(CTX, Int_val(domid), &c_info, 0); \
+	if (async != Val_none) {					\
+		p = malloc(sizeof(value));				\
+		*p = Some_val(async);					\
+		caml_register_global_root(p);				\
+		ao_how.callback = async_callback;			\
+		ao_how.u.for_callback = (void *) p;			\
+	}								\
+									\
+	ret = libxl_device_##type##_##op(CTX, Int_val(domid), &c_info,	\
+		async != Val_none ? &ao_how : NULL);			\
 									\
 	libxl_device_##type##_dispose(&c_info);				\
 									\
-- 
1.7.10.4