[PATCH v1 3/5] tools/ocaml/libs/xc: add hvm_param_get binding

[Edwin Török <edvin.torok@xxxxxxxxxx>]

Not to be confused which hvm_get_param, which also exists and has a
different, more error-prone interface.

This one always returns a 64-bit value, and that is retained in the
OCaml binding as well, returning 'int64' (and not int, or nativeint
which might have a different size).

The integer here is unsigned in the C API, however OCaml only has signed 
integers.

No bits are lost, it is just a matter of interpretation when printing
and for certain arithmetic operations, however in the cases where the
MSB is set it is very likely that the value is an address and no
arithmetic should be performed on the OCaml side on it.
(this is not a new problem with this binding, but worth mentioning given
the difference in types)

Signed-off-by: Edwin Török <edvin.torok@xxxxxxxxxx>
---
 tools/ocaml/libs/xc/xenctrl.ml      | 44 ++++++++++++++++++++++++++++
 tools/ocaml/libs/xc/xenctrl.mli     | 45 +++++++++++++++++++++++++++++
 tools/ocaml/libs/xc/xenctrl_stubs.c | 16 ++++++++++
 3 files changed, 105 insertions(+)

diff --git a/tools/ocaml/libs/xc/xenctrl.ml b/tools/ocaml/libs/xc/xenctrl.ml
index c21e391f98..1f8d927b0c 100644
--- a/tools/ocaml/libs/xc/xenctrl.ml
+++ b/tools/ocaml/libs/xc/xenctrl.ml
@@ -298,6 +298,50 @@ external map_foreign_range: handle -> domid -> int
   -> nativeint -> Xenmmap.mmap_interface
   = "stub_map_foreign_range"
 
+type hvm_param =
+  | HVM_PARAM_CALLBACK_IRQ
+  | HVM_PARAM_STORE_PFN
+  | HVM_PARAM_STORE_EVTCHN
+  | HVM_PARAM_UNDEFINED_3
+  | HVM_PARAM_PAE_ENABLED
+  | HVM_PARAM_IOREQ_PFN
+  | HVM_PARAM_BUFIOREQ_PFN
+  | HVM_PARAM_UNDEFINED_7
+  | HVM_PARAM_UNDEFINED_8
+  | HVM_PARAM_VIRIDIAN
+  | HVM_PARAM_TIMER_MODE0
+  | HVM_PARAM_HPET_ENABLED1
+  | HVM_PARAM_IDENT_PT2
+  | HVM_PARAM_UNDEFINED_13
+  | HVM_PARAM_ACPI_S_STATE4
+  | HVM_PARAM_VM86_TSS5
+  | HVM_PARAM_VPT_ALIGN6
+  | HVM_PARAM_CONSOLE_PFN7
+  | HVM_PARAM_CONSOLE_EVTCHN8
+  | HVM_PARAM_ACPI_IOPORTS_LOCATION9
+  | HVM_PARAM_MEMORY_EVENT_CR00
+  | HVM_PARAM_MEMORY_EVENT_CR31
+  | HVM_PARAM_MEMORY_EVENT_CR42
+  | HVM_PARAM_MEMORY_EVENT_INT33
+  | HVM_PARAM_NESTEDHVM4
+  | HVM_PARAM_MEMORY_EVENT_SINGLE_STEP5
+  | HVM_PARAM_UNDEFINED_26
+  | HVM_PARAM_PAGING_RING_PFN7
+  | HVM_PARAM_MONITOR_RING_PFN8
+  | HVM_PARAM_SHARING_RING_PFN9
+  | HVM_PARAM_MEMORY_EVENT_MSR0
+  | HVM_PARAM_TRIPLE_FAULT_REASON1
+  | HVM_PARAM_IOREQ_SERVER_PFN2
+  | HVM_PARAM_NR_IOREQ_SERVER_PAGES3
+  | HVM_PARAM_VM_GENERATION_ID_ADDR4
+  | HVM_PARAM_ALTP2M5
+  | HVM_PARAM_X87_FIP_WIDTH6
+  | HVM_PARAM_VM86_TSS_SIZED7
+  | HVM_PARAM_MCA_CAP8
+
+external hvm_param_get: handle -> domid -> hvm_param -> int64
+  = "stub_xc_hvm_param_get"
+
 external domain_assign_device: handle -> domid -> (int * int * int * int) -> 
unit
   = "stub_xc_domain_assign_device"
 external domain_deassign_device: handle -> domid -> (int * int * int * int) -> 
unit
diff --git a/tools/ocaml/libs/xc/xenctrl.mli b/tools/ocaml/libs/xc/xenctrl.mli
index 60e7902e66..f6c7e5b553 100644
--- a/tools/ocaml/libs/xc/xenctrl.mli
+++ b/tools/ocaml/libs/xc/xenctrl.mli
@@ -236,6 +236,51 @@ external map_foreign_range :
   handle -> domid -> int -> nativeint -> Xenmmap.mmap_interface
   = "stub_map_foreign_range"
 
+(* needs to be sorted according to its numeric value, watch out for gaps! *)
+type hvm_param =
+  | HVM_PARAM_CALLBACK_IRQ
+  | HVM_PARAM_STORE_PFN
+  | HVM_PARAM_STORE_EVTCHN
+  | HVM_PARAM_UNDEFINED_3
+  | HVM_PARAM_PAE_ENABLED
+  | HVM_PARAM_IOREQ_PFN
+  | HVM_PARAM_BUFIOREQ_PFN
+  | HVM_PARAM_UNDEFINED_7
+  | HVM_PARAM_UNDEFINED_8
+  | HVM_PARAM_VIRIDIAN
+  | HVM_PARAM_TIMER_MODE0
+  | HVM_PARAM_HPET_ENABLED1
+  | HVM_PARAM_IDENT_PT2
+  | HVM_PARAM_UNDEFINED_13
+  | HVM_PARAM_ACPI_S_STATE4
+  | HVM_PARAM_VM86_TSS5
+  | HVM_PARAM_VPT_ALIGN6
+  | HVM_PARAM_CONSOLE_PFN7
+  | HVM_PARAM_CONSOLE_EVTCHN8
+  | HVM_PARAM_ACPI_IOPORTS_LOCATION9
+  | HVM_PARAM_MEMORY_EVENT_CR00
+  | HVM_PARAM_MEMORY_EVENT_CR31
+  | HVM_PARAM_MEMORY_EVENT_CR42
+  | HVM_PARAM_MEMORY_EVENT_INT33
+  | HVM_PARAM_NESTEDHVM4
+  | HVM_PARAM_MEMORY_EVENT_SINGLE_STEP5
+  | HVM_PARAM_UNDEFINED_26
+  | HVM_PARAM_PAGING_RING_PFN7
+  | HVM_PARAM_MONITOR_RING_PFN8
+  | HVM_PARAM_SHARING_RING_PFN9
+  | HVM_PARAM_MEMORY_EVENT_MSR0
+  | HVM_PARAM_TRIPLE_FAULT_REASON1
+  | HVM_PARAM_IOREQ_SERVER_PFN2
+  | HVM_PARAM_NR_IOREQ_SERVER_PAGES3
+  | HVM_PARAM_VM_GENERATION_ID_ADDR4
+  | HVM_PARAM_ALTP2M5
+  | HVM_PARAM_X87_FIP_WIDTH6
+  | HVM_PARAM_VM86_TSS_SIZED7
+  | HVM_PARAM_MCA_CAP8
+
+external hvm_param_get: handle -> domid -> hvm_param -> int64
+  = "stub_xc_hvm_param_get"
+
 external domain_assign_device: handle -> domid -> (int * int * int * int) -> 
unit
   = "stub_xc_domain_assign_device"
 external domain_deassign_device: handle -> domid -> (int * int * int * int) -> 
unit
diff --git a/tools/ocaml/libs/xc/xenctrl_stubs.c 
b/tools/ocaml/libs/xc/xenctrl_stubs.c
index 67f3648391..b2df93d4f8 100644
--- a/tools/ocaml/libs/xc/xenctrl_stubs.c
+++ b/tools/ocaml/libs/xc/xenctrl_stubs.c
@@ -1176,6 +1176,22 @@ CAMLprim value stub_xc_domain_irq_permission(value xch, 
value domid,
     CAMLreturn(Val_unit);
 }
 
+CAMLprim value stub_xc_hvm_param_get(value xch, value domid, value param)
+{
+    CAMLparam3(xch, domid, param);
+    uint64_t result;
+    int ret;
+
+    caml_enter_blocking_section();
+    ret = xc_hvm_param_get(_H(xch), _D(domid), Int_val(param), &result);
+    caml_leave_blocking_section();
+
+    if ( ret )
+        failwith_xc(_H(xch));
+
+    CAMLreturn(caml_copy_int64(result));
+}
+
 static uint32_t encode_sbdf(int domain, int bus, int dev, int func)
 {
     return  ((uint32_t)domain & 0xffff) << 16 |
-- 
2.34.1