configure: Add wrappers for default make request function

Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>

configure.d/1_default_make_request.conf

@@ -0,0 +1,54 @@
+#!/bin/bash
+#
+# Copyright(c) 2012-2020 Intel Corporation
+# SPDX-License-Identifier: BSD-3-Clause-Clear
+#
+
+. $(dirname $3)/conf_framework
+
+check() {
+    cur_name=$(basename $2)
+    config_file_path=$1
+    if compile_module $cur_name "blk_mq_make_request(NULL, NULL);" "linux/blk-mq.h"
+    then
+        echo $cur_name "1" >> $config_file_path
+    else
+        echo $cur_name "2" >> $config_file_path
+    fi
+}
+
+apply() {
+    case "$1" in
+    "1")
+        add_function "
+        static inline void *cas_get_default_mk_request_fn(struct request_queue *q)
+        {
+            if (q->make_request_fn)
+                return q->make_request_fn;
+            return blk_mq_make_request;
+        }"
+        add_function "
+        static inline void cas_call_default_mk_request_fn(make_request_fn *fn,
+            struct request_queue *q, struct bio *bio)
+        {
+            percpu_ref_get(&q->q_usage_counter);
+            fn(q, bio);
+        }" ;;
+    "2")
+        add_function "
+        static inline void *cas_get_default_mk_request_fn(struct request_queue *q)
+        {
+            return q->make_request_fn;
+        }"
+        add_function "
+        static inline void cas_call_default_mk_request_fn(make_request_fn *fn,
+            struct request_queue *q, struct bio *bio)
+        {
+            fn(q, bio);
+        }" ;;
+    *)
+        exit 1
+    esac
+}
+
+conf_run $@

modules/cas_disk/exp_obj.c

@@ -77,7 +77,7 @@ static inline void _casdsk_exp_obj_handle_bio_att(struct casdsk_disk *dsk,
 				make_request_fn(dsk, q, bio, dsk->private);
 
 	if (status == CASDSK_BIO_NOT_HANDLED)
-		dsk->exp_obj->mk_rq_fn(q, bio);
+		cas_call_default_mk_request_fn(dsk->exp_obj->mk_rq_fn, q, bio);
 }
 
 CAS_DECLARE_BLOCK_CALLBACK(_casdsk_exp_obj_bio_pt_io, struct bio *bio,
@@ -573,7 +573,7 @@ int casdsk_exp_obj_create(struct casdsk_disk *dsk, const char *dev_name,
 	gd->private_data = dsk;
 	strlcpy(gd->disk_name, exp_obj->dev_name, sizeof(gd->disk_name));
 
-	dsk->exp_obj->mk_rq_fn = queue->make_request_fn;
+	dsk->exp_obj->mk_rq_fn = cas_get_default_mk_request_fn(queue);
 	cas_blk_queue_make_request(queue, _casdsk_exp_obj_make_rq_fn);
 
 	if (exp_obj->ops->set_geometry) {