[From REQ-477] Cherry-pick addition of iSCSI IQN and multipathing changes

ocaml/idl/datamodel_host.ml

@@ -1235,6 +1235,28 @@ let host_query_ha = call ~flags:[`Session]
       ~allowed_roles:_R_VM_OP
       ()
 
+  let set_iscsi_iqn = call
+    ~name:"set_iscsi_iqn"
+    ~lifecycle:[Published, rel_kolkata, ""]
+    ~doc:"Sets the initiator IQN for the host"
+    ~params:[
+      Ref _host, "host", "The host";
+      String, "value", "The value to which the IQN should be set"
+    ]
+    ~allowed_roles:_R_POOL_OP
+    ()
+
+  let set_multipathing = call
+    ~name:"set_multipathing"
+    ~lifecycle:[Published, rel_kolkata, ""]
+    ~doc:"Specifies whether multipathing is enabled"
+    ~params:[
+      Ref _host, "host", "The host";
+      Bool, "value", "Whether multipathing should be enabled"
+    ]
+    ~allowed_roles:_R_POOL_OP
+    ()
+
   (** Hosts *)
   let t =
     create_obj ~in_db:true ~in_product_since:rel_rio ~in_oss_since:oss_since_303 ~internal_deprecated_since:None ~persist:PersistEverything ~gen_constructor_destructor:false ~name:_host ~descr:"A physical host" ~gen_events:true
@@ -1346,6 +1368,8 @@ let host_query_ha = call ~flags:[`Session]
         apply_guest_agent_config;
         mxgpu_vf_setup;
         allocate_resources_for_vm;
+        set_iscsi_iqn;
+        set_multipathing;
       ]
       ~contents:
         ([ uid _host;
@@ -1400,6 +1424,8 @@ let host_query_ha = call ~flags:[`Session]
            field ~qualifier:DynamicRO ~in_product_since:rel_cream ~default_value:(Some (VSet [VInt 0L])) ~ty:(Set (Int)) "virtual_hardware_platform_versions" "The set of versions of the virtual hardware platform that the host can offer to its guests";
            field ~qualifier:DynamicRO ~default_value:(Some (VRef null_ref)) ~in_product_since:rel_ely ~ty:(Ref _vm) "control_domain" "The control domain (domain 0)";
            field ~qualifier:DynamicRO ~lifecycle:[Published, rel_ely, ""] ~ty:(Set (Ref _pool_update)) ~ignore_foreign_key:true "updates_requiring_reboot" "List of updates which require reboot";
-           field ~qualifier:DynamicRO ~lifecycle:[Published, rel_falcon, ""] ~ty:(Set (Ref _feature)) "features" "List of features available on this host"
+           field ~qualifier:DynamicRO ~lifecycle:[Published, rel_falcon, ""] ~ty:(Set (Ref _feature)) "features" "List of features available on this host";
+           field ~qualifier:StaticRO ~lifecycle:[Published, rel_kolkata, ""] ~default_value:(Some (VString "")) ~ty:String "iscsi_iqn" "The initiator IQN for the host";
+           field ~qualifier:StaticRO ~lifecycle:[Published, rel_kolkata, ""] ~default_value:(Some (VBool false)) ~ty:Bool "multipathing" "Specifies whether multipathing is enabled";
          ])
       ()

ocaml/tests/suite.ml

@@ -62,6 +62,7 @@ let base_suite =
     Test_network_event_loop.test;
     Test_network.test;
     Test_pusb.test;
+    Test_host_helpers.test;
   ]
 
 let () =

ocaml/tests/test_common.ml

@@ -151,7 +151,9 @@ let make_host2 ~__context ?(ref=Ref.make ()) ?(uuid=make_uuid ()) ?(name_label="
     ~display:`enabled
     ~virtual_hardware_platform_versions:[]
     ~control_domain:Ref.null
-    ~updates_requiring_reboot:[];
+    ~updates_requiring_reboot:[]
+    ~iscsi_iqn:""
+    ~multipathing:false;
   ref
 
 let make_pif ~__context ~network ~host ?(device="eth0") ?(mAC="C0:FF:EE:C0:FF:EE") ?(mTU=1500L)

ocaml/tests/test_host_helpers.ml

@@ -0,0 +1,126 @@
+(*
+ * Copyright (C) Citrix Systems Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published
+ * by the Free Software Foundation; version 2.1 only. with the special
+ * exception on linking described in file LICENSE.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *)
+
+open OUnit
+
+let setup_test_oc_watcher () =
+  let __context, _ = Test_event_common.event_setup_common () in
+  let calls = ref [] in
+  let test_rpc call =
+    match call.Rpc.name, call.Rpc.params with
+    | "host.set_iscsi_iqn", [_session_id_rpc;host_rpc;value_rpc] ->
+      let host = API.ref_host_of_rpc host_rpc in
+      let v = API.string_of_rpc value_rpc in
+      Db.Host.set_iscsi_iqn ~__context ~self:host ~value:v;
+      calls := (host,`set_iscsi_iqn v) :: !calls;
+      Rpc.{success=true; contents=Rpc.String ""}
+    | "host.set_multipathing", [_session_id_rpc;host_rpc;value_rpc] ->
+      let host = API.ref_host_of_rpc host_rpc in
+      let v = API.bool_of_rpc value_rpc in
+      Db.Host.set_multipathing ~__context ~self:host ~value:v;
+      calls := (host,`set_multipathing v) :: !calls;
+      Rpc.{success=true; contents=Rpc.String ""}
+    | _ -> Mock_rpc.rpc __context call
+  in
+  Context.set_test_rpc __context test_rpc;
+  let host1 = !Xapi_globs.localhost_ref in
+  let host2 = Test_common.make_host ~__context () in
+  let watcher = Xapi_host_helpers.Configuration.watch_other_configs ~__context 0.0 in
+  let token = watcher "" in
+  (__context, calls, host1, host2, watcher, token)
+
+let test_host1 () =
+  (* Test1: update other_config:iscsi_iqn,multipathing on host1, check they appear in the calls list *)
+  let (__context, calls, host1, host2, watcher, token) = setup_test_oc_watcher () in
+  Db.Host.set_multipathing ~__context ~self:host1 ~value:false;
+
+  Db.Host.add_to_other_config ~__context ~self:host1 ~key:"iscsi_iqn" ~value:"test1";
+  let token = watcher token in
+  assert_equal !calls [host1, `set_iscsi_iqn "test1"];
+
+  calls := [];
+  Db.Host.add_to_other_config ~__context ~self:host1 ~key:"multipathing" ~value:"true";
+  let _token = watcher token in
+  assert_equal !calls [host1, `set_multipathing true]
+
+let test_host2 () =
+  (* Test2: update other_config:iscsi_iqn,multipathing on host2, check they appear in the calls list *)
+  let (__context, calls, host1, host2, watcher, token) = setup_test_oc_watcher () in
+  Db.Host.set_multipathing ~__context ~self:host2 ~value:true;
+
+  Db.Host.add_to_other_config ~__context ~self:host2 ~key:"iscsi_iqn" ~value:"test2";
+  let token = watcher token in
+  assert_equal !calls [host2, `set_iscsi_iqn "test2"];
+
+  calls := [];
+  Db.Host.add_to_other_config ~__context ~self:host2 ~key:"multipathing" ~value:"false";
+  let _token = watcher token in
+  assert_equal !calls [host2, `set_multipathing false]
+
+let test_different_keys () =
+  (* Test3: verify that setting other other-config keys causes no set *)
+  let (__context, calls, host1, host2, watcher, token) = setup_test_oc_watcher () in
+  Db.Host.add_to_other_config ~__context ~self:host1 ~key:"other_key" ~value:"test1";
+  let _token = watcher token in
+  assert_equal !calls []
+
+let test_host_set_iscsi_iqn () =
+  (* Test3: verify that sequence of DB calls in Host.set_iscsi_iqn don't cause the
+     watcher to invoke further calls *)
+  let (__context, calls, host1, host2, watcher, token) = setup_test_oc_watcher () in
+  Db.Host.add_to_other_config ~__context ~self:host1 ~key:"iscsi_iqn" ~value:"test1";
+  let token = watcher token in
+  assert_equal !calls [host1, `set_iscsi_iqn "test1"];
+  calls := [];
+  Db.Host.remove_from_other_config ~__context ~self:host1 ~key:"iscsi_iqn";
+  let token = watcher token in
+  assert_equal !calls [];
+  Db.Host.set_iscsi_iqn ~__context ~self:host1 ~value:"test2";
+  let token = watcher token in
+  assert_equal !calls [];
+  Db.Host.add_to_other_config ~__context ~self:host1 ~key:"iscsi_iqn" ~value:"test2";
+  let _token = watcher token in
+  assert_equal !calls []
+
+let test_host_set_multipathing () =
+  (* Test3: verify that sequence of DB calls in Host.set_multipathing don't cause the
+     watcher to invoke further calls *)
+  let (__context, calls, host1, host2, watcher, token) = setup_test_oc_watcher () in
+  Db.Host.set_multipathing ~__context ~self:host2 ~value:false;
+
+  Db.Host.add_to_other_config ~__context ~self:host1 ~key:"multipathing" ~value:"true";
+  let token = watcher token in
+  assert_equal !calls [host1, `set_multipathing true];
+  calls := [];
+
+  Db.Host.remove_from_other_config ~__context ~self:host1 ~key:"multipathing";
+  let token = watcher token in
+  assert_equal !calls [];
+  Db.Host.set_multipathing ~__context ~self:host1 ~value:false;
+  let token = watcher token in
+  assert_equal !calls [];
+  Db.Host.add_to_other_config ~__context ~self:host1 ~key:"multipathing" ~value:"false";
+  let _token = watcher token in
+  assert_equal !calls []
+
+
+let test =
+  "other_config_watcher" >:::
+  [
+    "test_host1" >:: test_host1;
+    "test_host2" >:: test_host2;
+    "test_different_keys" >:: test_different_keys;
+    "test_host_set_iscsi_iqn" >:: test_host_set_iscsi_iqn;
+    "test_host_set_multipathing" >:: test_host_set_multipathing;
+  ]

ocaml/tests/test_sm_features.ml

@@ -157,6 +157,16 @@ let test_sequences =
         features = ["VDI_RESIZE", 1L];
       };
     };
+    (* Test SMAPIV3 SR_MULTIPATH feature *)
+    {
+      raw = ["SR_MULTIPATH"];
+      smapiv1_features = [Sr_multipath, 1L];
+      smapiv2_features = ["SR_MULTIPATH/1"];
+      sm = {
+        capabilities = ["SR_MULTIPATH"];
+        features = ["SR_MULTIPATH", 1L];
+      };
+    }
   ]
 
 module ParseSMAPIv1Features = Generic.Make(struct

ocaml/xapi/message_forwarding.ml

@@ -2654,6 +2654,20 @@ module Forward = functor(Local: Custom_actions.CUSTOM_ACTIONS) -> struct
         (host_uuid ~__context self) (vm_uuid ~__context vm);
       let snapshot = Db.VM.get_record ~__context ~self:vm in
       VM.allocate_vm_to_host ~__context ~vm ~host:self ~snapshot ()
+
+    let set_iscsi_iqn ~__context ~host ~value =
+      info "Host.set_iscsi_iqn: host='%s' iqn='%s'" (host_uuid ~__context host) value;
+      let local_fn = Local.Host.set_iscsi_iqn ~host ~value in
+      do_op_on ~local_fn ~__context ~host
+        (fun session_id rpc ->
+          Client.Host.set_iscsi_iqn rpc session_id host value)
+
+    let set_multipathing ~__context ~host ~value =
+      info "Host.set_multipathing: host='%s' value='%s'" (host_uuid ~__context host) (string_of_bool value);
+      let local_fn = Local.Host.set_multipathing ~host ~value in
+      do_op_on ~local_fn ~__context ~host
+        (fun session_id rpc ->
+          Client.Host.set_multipathing rpc session_id host value)
   end
 
   module Host_crashdump = struct

ocaml/xapi/records.ml

@@ -1249,6 +1249,10 @@ let host_record rpc session_id host =
       make_field ~name:"features"
         ~get:(fun () -> String.concat "; " (List.map get_uuid_from_ref (x ()).API.host_features))
         ~get_set:(fun () -> List.map get_uuid_from_ref (x ()).API.host_features) ();
+      make_field ~name:"iscsi_iqn"
+        ~get:(fun () -> (x ()).API.host_iscsi_iqn) ~set:(fun s -> Client.Host.set_iscsi_iqn rpc session_id host s) ();
+      make_field ~name:"multipathing"
+        ~get:(fun () -> string_of_bool (x ()).API.host_multipathing) ~set:(fun s -> Client.Host.set_multipathing rpc session_id host (safe_bool_of_string "multipathing" s)) ();
     ]}
 
 let vdi_record rpc session_id vdi =

ocaml/xapi/smint.ml

@@ -30,6 +30,7 @@ type capability =
   | Sr_stats
   | Sr_metadata
   | Sr_trim
+  | Sr_multipath
   | Vdi_create | Vdi_delete | Vdi_attach | Vdi_detach | Vdi_mirror
   | Vdi_clone | Vdi_snapshot | Vdi_resize | Vdi_activate | Vdi_deactivate
   | Vdi_update | Vdi_introduce
@@ -47,6 +48,7 @@ let string_to_capability_table = [
   "SR_SUPPORTS_LOCAL_CACHING", Sr_supports_local_caching;
   "SR_METADATA",    Sr_metadata;
   "SR_TRIM",        Sr_trim;
+  "SR_MULTIPATH",   Sr_multipath;
   "VDI_CREATE",     Vdi_create;
   "VDI_DELETE",     Vdi_delete;
   "VDI_ATTACH",     Vdi_attach;

ocaml/xapi/xapi.ml

@@ -818,6 +818,8 @@ let server_init() =
           "hi-level database upgrade", [ Startup.OnlyMaster ], Xapi_db_upgrade.hi_level_db_upgrade_rules ~__context;
           "bringing up management interface", [], bring_up_management_if ~__context;
           "Starting periodic scheduler", [Startup.OnThread], Xapi_periodic_scheduler.loop;
+          "Synchronising host configuration files", [], (fun () -> Xapi_host_helpers.Configuration.sync_config_files ~__context);
+          "Starting Host other-config watcher", [Startup.OnlyMaster], (fun () -> Xapi_host_helpers.Configuration.start_watcher_thread ~__context);
           "Remote requests", [Startup.OnThread], Remote_requests.handle_requests;
         ];
         begin match Pool_role.get_role () with

ocaml/xapi/xapi_globs.ml

@@ -761,6 +761,9 @@ let udhcpd_skel = ref (Filename.concat "/etc/xensource" "udhcpd.skel")
 let udhcpd_leases_db = ref "/var/lib/xcp/dhcp-leases.db"
 let udhcpd_pidfile = ref "/var/run/udhcpd.pid"
 
+let iscsi_initiator_config_file = ref "/etc/iscsi/initiatorname.iscsi"
+let multipathing_config_file = ref "/var/run/nonpersistent/multipath_enabled"
+
 let busybox = ref "busybox"
 
 let xe_path = ref "xe"
@@ -1112,6 +1115,7 @@ module Resources = struct
     "logconfig", log_config_file, "Configure the logging policy";
     "cpu-info-file", cpu_info_file, "Where to cache boot-time CPU info";
     "server-cert-path", server_cert_path, "Path to server ssl certificate";
+    "iscsi_initiatorname", iscsi_initiator_config_file, "Path to the initiatorname.iscsi file"
   ]
   let essential_dirs = [
     "sm-dir", sm_dir, "Directory containing SM plugins";

ocaml/xapi/xapi_host.ml

@@ -645,6 +645,8 @@ let create ~__context ~uuid ~name_label ~name_description ~hostname ~address ~ex
     ~virtual_hardware_platform_versions:(if host_is_us then Xapi_globs.host_virtual_hardware_platform_versions else [0L])
     ~control_domain:Ref.null
     ~updates_requiring_reboot:[]
+    ~iscsi_iqn:""
+    ~multipathing:false
   ;
   (* If the host we're creating is us, make sure its set to live *)
   Db.Host_metrics.set_last_updated ~__context ~self:metrics ~value:(Date.of_float (Unix.gettimeofday ()));
@@ -1766,3 +1768,31 @@ let mxgpu_vf_setup ~__context ~host =
 let allocate_resources_for_vm ~__context ~self ~vm ~live =
   (* Implemented entirely in Message_forwarding *)
   ()
+
+let set_iscsi_iqn ~__context ~host ~value =
+  if value = "" then raise Api_errors.(Server_error (invalid_value, ["value"; value]));
+  (* Note, the following sequence is carefully written - see the
+     other-config watcher thread in xapi_host_helpers.ml *)
+  Db.Host.remove_from_other_config ~__context ~self:host ~key:"iscsi_iqn";
+  (* we need to first set the iscsi_iqn field and then the other-config field:
+   * setting the other-config field triggers and update on the iscsi_iqn
+   * field if they are different
+   *
+   * we want to keep the legacy `other_config:iscsi_iqn` and the new `iscsi_iqn`
+   * fields in sync:
+   * when you update the `iscsi_iqn` field we want to update `other_config`,
+   * but when updating `other_config` we want to update `iscsi_iqn` too.
+   * we have to be careful not to introduce an infinite loop of updates.
+   * *)
+  Db.Host.set_iscsi_iqn ~__context ~self:host ~value;
+  Db.Host.add_to_other_config ~__context ~self:host ~key:"iscsi_iqn" ~value;
+  Xapi_host_helpers.Configuration.set_initiator_name value
+
+let set_multipathing ~__context ~host ~value =
+  (* Note, the following sequence is carefully written - see the
+     other-config watcher thread in xapi_host_helpers.ml *)
+  Db.Host.remove_from_other_config ~__context ~self:host ~key:"multipathing";
+  Db.Host.set_multipathing ~__context ~self:host ~value;
+  Db.Host.add_to_other_config ~__context ~self:host ~key:"multipathing" ~value:(string_of_bool value);
+  Xapi_host_helpers.Configuration.set_multipathing value
+

ocaml/xapi/xapi_host.mli

@@ -310,3 +310,5 @@ val apply_guest_agent_config : __context:Context.t -> host:API.ref_host -> unit
 val mxgpu_vf_setup : __context:Context.t -> host:API.ref_host -> unit
 
 val allocate_resources_for_vm : __context:Context.t -> self:API.ref_host -> vm:API.ref_VM -> live:bool -> unit
+val set_iscsi_iqn : __context:Context.t -> host:API.ref_host -> value:string -> unit
+val set_multipathing : __context:Context.t -> host:API.ref_host -> value:bool -> unit