[PATCH v4 08/10] tools/ocaml/libs/xc: add OCaml domain_claim_memory binding

[Bernhard Kaindl <bernhard.kaindl@xxxxxxxxxx>]

Add OCaml bindings for xc_domain_claim_memory(), for using the
XEN_DOMCTL_claim_memory hypercall from OCaml. This allows OCaml
toolstacks to place NUMA-aware memory claims for domains as well
as host-wide claims.

tools/ocaml/libs/xc/xenctrl.ml/mli:
- Add claim record type and domain_claim_memory external.

tools/ocaml/libs/xc/xenctrl_stubs.c:
- Validate claim count and arguments.
- Marshal the OCaml claim array to memory_claim_t[].
- Map node = -1 to XEN_DOMCTL_CLAIM_MEMORY_NO_NODE.

Signed-off-by: Bernhard Kaindl <bernhard.kaindl@xxxxxxxxxx>
---
 tools/ocaml/libs/xc/xenctrl.ml      | 11 ++++++++
 tools/ocaml/libs/xc/xenctrl.mli     | 11 ++++++++
 tools/ocaml/libs/xc/xenctrl_stubs.c | 43 +++++++++++++++++++++++++++++
 3 files changed, 65 insertions(+)

diff --git a/tools/ocaml/libs/xc/xenctrl.ml b/tools/ocaml/libs/xc/xenctrl.ml
index 97108b9d861a..a1a05dcaede3 100644
--- a/tools/ocaml/libs/xc/xenctrl.ml
+++ b/tools/ocaml/libs/xc/xenctrl.ml
@@ -370,6 +370,17 @@ external domain_deassign_device: handle -> domid -> (int * 
int * int * int) -> u
 external domain_test_assign_device: handle -> domid -> (int * int * int * int) 
-> bool
   = "stub_xc_domain_test_assign_device"
 
+(* OCaml binding for xc_domain_claim_memory(): claim pages for a domain,
+   optionally per NUMA node (node = -1 means no specific node). *)
+
+type claim =
+  {
+    pages: int64;  (* Number of pages to claim *)
+    node: int32;   (* NUMA node ID, or -1 for no specific node *)
+  }
+external domain_claim_memory: handle -> domid -> claim array -> unit
+  = "stub_xc_domain_claim_memory"
+
 external version: handle -> version = "stub_xc_version_version"
 external version_compile_info: handle -> compile_info
   = "stub_xc_version_compile_info"
diff --git a/tools/ocaml/libs/xc/xenctrl.mli b/tools/ocaml/libs/xc/xenctrl.mli
index 9fccb2c2c287..1781c89258fe 100644
--- a/tools/ocaml/libs/xc/xenctrl.mli
+++ b/tools/ocaml/libs/xc/xenctrl.mli
@@ -297,6 +297,17 @@ external domain_deassign_device: handle -> domid -> (int * 
int * int * int) -> u
 external domain_test_assign_device: handle -> domid -> (int * int * int * int) 
-> bool
   = "stub_xc_domain_test_assign_device"
 
+(* OCaml binding for xc_domain_claim_memory(): claim pages for a domain,
+   optionally per NUMA node (node = -1 means no specific node). *)
+
+type claim =
+  {
+    pages: int64;  (* Number of pages to claim *)
+    node: int32;   (* NUMA node ID, or -1 for no specific node *)
+  }
+external domain_claim_memory: handle -> domid -> claim array -> unit
+  = "stub_xc_domain_claim_memory"
+
 external version : handle -> version = "stub_xc_version_version"
 external version_compile_info : handle -> compile_info
   = "stub_xc_version_compile_info"
diff --git a/tools/ocaml/libs/xc/xenctrl_stubs.c 
b/tools/ocaml/libs/xc/xenctrl_stubs.c
index c55f73b265b2..a77d7dac58e8 100644
--- a/tools/ocaml/libs/xc/xenctrl_stubs.c
+++ b/tools/ocaml/libs/xc/xenctrl_stubs.c
@@ -1435,6 +1435,49 @@ CAMLprim value stub_xc_watchdog(value xch_val, value 
domid, value timeout)
        CAMLreturn(Val_int(ret));
 }
 
+CAMLprim value stub_xc_domain_claim_memory(value xch_val, value domid,
+                                           value claims)
+{
+       CAMLparam3(xch_val, domid, claims);
+       xc_interface *xch = xch_of_val(xch_val);
+       mlsize_t nr_claims = Wosize_val(claims);
+       memory_claim_t *claim;
+       int retval;
+
+       if (nr_claims > XEN_DOMCTL_MAX_CLAIMS)
+               caml_invalid_argument("domain_claim_memory: too many claims");
+
+       claim = calloc(nr_claims, sizeof(*claim));
+       if (claim == NULL && nr_claims != 0)
+               caml_raise_out_of_memory();
+
+       for (mlsize_t i = 0; i < nr_claims; i++) {
+               value claim_rec = Field(claims, i);
+               int64_t pages = Int64_val(Field(claim_rec, 0));
+               int32_t node = Int32_val(Field(claim_rec, 1));
+               uint32_t c_node;
+
+               if (pages < 0 || node < -1 ) {
+                       free(claim);
+                       caml_invalid_argument("domain_claim_memory: invalid 
pages or node");
+               }
+
+               if (node == -1)
+                       c_node = XEN_DOMCTL_CLAIM_MEMORY_NO_NODE;
+               else
+                       c_node = node;
+
+               claim[i] = (memory_claim_t)XEN_NODE_CLAIM_INIT((uint64_t)pages, 
c_node);
+       }
+
+       retval = xc_domain_claim_memory(xch, Int_val(domid), nr_claims, claim);
+       free(claim);
+       if (retval < 0)
+               failwith_xc(xch);
+
+       CAMLreturn(Val_unit);
+}
+
 /*
  * Local variables:
  *  indent-tabs-mode: t
-- 
2.39.5