Merge pull request #95 from micrakow/block_layer_return_types

Return values of expected type by the block layer

configure

@@ -61,11 +61,9 @@ generate_header() {
 	echo "Configuring OpenCAS"
 	for file in $FIRST; do
 		CONF=$(cat ${CONFIG_FILE} | grep $(basename $file) | cut -d' ' -f2)
-		source $file "apply" "$CONF" "$file" &
+		source $file "apply" "$CONF" "$file"
 	done
 
-	wait
-
 	for file in $SECOND; do
 		CONF=$(cat ${CONFIG_FILE} | grep $(basename $file) | cut -d' ' -f2)
 		source $file "apply" "$CONF" "$file"

configure.d/1_bio_err.conf

@@ -15,6 +15,11 @@ check() {
 	elif compile_module $cur_name "struct bio b;b.bi_error" "linux/bio.h"
 	then
 		echo $cur_name "2" >> $config_file_path
+	elif compile_module $cur_name "bio_endio(NULL, 0)" "linux/bio.h"
+	then
+		echo $cur_name "3" >> $config_file_path
+	else
+		echo $cur_name "X" >> $config_file_path
 	fi
 }
 
@@ -26,6 +31,10 @@ apply() {
     "2")
 		add_define "CAS_BIO_OP_STATUS(bio) \\
 			bio->bi_error" ;;
+    "3")
+	        # If bio_endio is available, we do not need to provide our own status accessors.
+	        # This case-switch prevents false errors during executing 'configure' script.
+	    	return 0 ;;
     *)
         exit 1
     esac

configure.d/1_blk_status.conf

@@ -20,9 +20,12 @@ check() {
 apply() {
     case "$1" in
     "1")
-		add_define "CAS_BLK_STATUS_T blk_status_t" ;;
+		add_define "CAS_BLK_STATUS_T blk_status_t"
+		add_define "CAS_BLK_STS_OK BLK_STS_OK" ;;
     "2")
-		add_define "CAS_BLK_STATUS_T int" ;;
+		add_define "CAS_BLK_STATUS_T int"
+		add_define "CAS_BLK_STS_OK 0" ;;
+
     *)
         exit 1
     esac

configure.d/1_err_no_to_blk_sts.conf

@@ -0,0 +1,31 @@
+#!/bin/bash
+#
+# Copyright(c) 2012-2019 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 "errno_to_blk_status(0)" "linux/blkdev.h"
+	then
+		echo $cur_name "1" >> $config_file_path
+	else
+		echo $cur_name "2" >> $config_file_path
+    fi
+}
+
+apply() {
+    case "$1" in
+    "1")
+		add_define "CAS_ERRNO_TO_BLK_STS(status) errno_to_blk_status(status)" ;;
+    "2")
+		add_define "CAS_ERRNO_TO_BLK_STS(status) status" ;;
+    *)
+        exit 1
+    esac
+}
+
+conf_run $@

configure.d/1_wtlh.conf

@@ -12,6 +12,8 @@ check() {
 	if compile_module $cur_name "struct bio b;b.bi_write_hint" "linux/bio.h"
 	then
 		echo $cur_name "1" >> $config_file_path
+	else
+		echo $cur_name "2" >> $config_file_path
 	fi
 }
 
@@ -20,6 +22,8 @@ apply() {
 	"1")
 		add_define "CAS_WLTH_SUPPORT \\
 			1" ;;
+	"2")
+		return 0 ;;
 	*)
 		exit 1
 	esac

configure.d/conf_framework

@@ -73,10 +73,14 @@ kernel_not_supp_fail() {
 # $2 - path to file with valid configs
 # $3 - name of processed template file
 conf_run() {
+	local OLD_IFS=$IFS
+	IFS='?'
+
 	case "$1" in
 		"check") check $2 $3;;
 		"apply") apply $2 ;;
 	esac
+
+	IFS=$OLD_IFS
 }
 
-IFS='?'

modules/cas_cache/volume/vol_block_dev_top.c

@@ -11,7 +11,8 @@
 
 static inline void _blockdev_end_request_all(struct request *rq, int error)
 {
-	CAS_END_REQUEST_ALL(rq, map_cas_err_to_generic(error));
+	CAS_END_REQUEST_ALL(rq, CAS_ERRNO_TO_BLK_STS(
+					map_cas_err_to_generic(error)));
 }
 
 static inline bool _blockdev_can_handle_rq(struct request *rq)
@@ -90,7 +91,7 @@ void block_dev_complete_bio_fast(struct ocf_io *io, int error)
 
 	_blockdev_end_io_acct(bio, data->start_time);
 
-	CAS_BIO_ENDIO(bio, CAS_BIO_BISIZE(bio), error);
+	CAS_BIO_ENDIO(bio, CAS_BIO_BISIZE(bio), CAS_ERRNO_TO_BLK_STS(error));
 	ocf_io_put(io);
 	cas_free_blk_data(data);
 }
@@ -99,7 +100,7 @@ void block_dev_complete_bio_discard(struct ocf_io *io, int error)
 {
 	struct bio *bio = io->priv1;
 
-	CAS_BIO_ENDIO(bio, CAS_BIO_BISIZE(bio), error);
+	CAS_BIO_ENDIO(bio, CAS_BIO_BISIZE(bio), CAS_ERRNO_TO_BLK_STS(error));
 	ocf_io_put(io);
 }
 
@@ -487,16 +488,14 @@ static int __block_dev_queue_rq(struct request *rq, ocf_core_t core)
 	return ret;
 }
 
-static int _block_dev_queue_request(struct casdsk_disk *dsk, struct request *rq, void *private)
+static CAS_BLK_STATUS_T _block_dev_queue_request(struct casdsk_disk *dsk, struct request *rq, void *private)
 {
 	ocf_core_t core = private;
-	int ret;
+	int ret = __block_dev_queue_rq(rq, core);
-
-	ret = __block_dev_queue_rq(rq, core);
 	if (ret)
 		_blockdev_end_request_all(rq, ret);
 
-	return ret;
+	return CAS_ERRNO_TO_BLK_STS(ret);
 }
 
 static inline int _blkdev_can_hndl_bio(struct bio *bio)
@@ -504,7 +503,7 @@ static inline int _blkdev_can_hndl_bio(struct bio *bio)
 	if (CAS_CHECK_BARRIER(bio)) {
 		CAS_PRINT_RL(KERN_WARNING
 			"special bio was sent, not supported!\n");
-		CAS_BIO_ENDIO(bio, CAS_BIO_BISIZE(bio), -EOPNOTSUPP);
+		CAS_BIO_ENDIO(bio, CAS_BIO_BISIZE(bio), CAS_ERRNO_TO_BLK_STS(-EOPNOTSUPP));
 		return -ENOTSUPP;
 	}
 
@@ -708,7 +707,7 @@ static void _blockdev_make_request_discard(struct casdsk_disk *dsk,
 	if (!io) {
 		CAS_PRINT_RL(KERN_CRIT
 			"Out of memory. Ending IO processing.\n");
-		CAS_BIO_ENDIO(bio, CAS_BIO_BISIZE(bio), -ENOMEM);
+		CAS_BIO_ENDIO(bio, CAS_BIO_BISIZE(bio), CAS_ERRNO_TO_BLK_STS(-ENOMEM));
 		return;
 	}
 
@@ -750,14 +749,14 @@ static int _blockdev_make_request_fast(struct casdsk_disk *dsk,
 		CAS_PRINT_RL(KERN_ERR
 			"Not able to handle empty BIO, flags = "
 			CAS_BIO_OP_FLAGS_FORMAT "\n",  CAS_BIO_OP_FLAGS(bio));
-		CAS_BIO_ENDIO(bio, CAS_BIO_BISIZE(bio), -EINVAL);
+		CAS_BIO_ENDIO(bio, CAS_BIO_BISIZE(bio), CAS_ERRNO_TO_BLK_STS(-EINVAL));
 		return CASDSK_BIO_HANDLED;
 	}
 
 	data = cas_alloc_blk_data(bio_segments(bio), GFP_ATOMIC);
 	if (!data) {
 		CAS_PRINT_RL(KERN_CRIT "BIO data vector allocation error\n");
-		CAS_BIO_ENDIO(bio, CAS_BIO_BISIZE(bio), -ENOMEM);
+		CAS_BIO_ENDIO(bio, CAS_BIO_BISIZE(bio), CAS_ERRNO_TO_BLK_STS(-ENOMEM));
 		return CASDSK_BIO_HANDLED;
 	}
 
@@ -775,7 +774,7 @@ static int _blockdev_make_request_fast(struct casdsk_disk *dsk,
 	if (!io) {
 		printk(KERN_CRIT "Out of memory. Ending IO processing.\n");
 		cas_free_blk_data(data);
-		CAS_BIO_ENDIO(bio, CAS_BIO_BISIZE(bio), -ENOMEM);
+		CAS_BIO_ENDIO(bio, CAS_BIO_BISIZE(bio), CAS_ERRNO_TO_BLK_STS(-ENOMEM));
 		return CASDSK_BIO_HANDLED;
 	}
 
@@ -783,7 +782,7 @@ static int _blockdev_make_request_fast(struct casdsk_disk *dsk,
 	if (ret < 0) {
 		ocf_io_put(io);
 		cas_free_blk_data(data);
-		CAS_BIO_ENDIO(bio, CAS_BIO_BISIZE(bio), -EINVAL);
+		CAS_BIO_ENDIO(bio, CAS_BIO_BISIZE(bio), CAS_ERRNO_TO_BLK_STS(-EINVAL));
 		return CASDSK_BIO_HANDLED;
 	}
 

modules/cas_disk/cas_disk.h

@@ -6,6 +6,7 @@
 #define __CASDISK_H__
 
 #include <linux/blkdev.h>
+#include "linux_kernel_version.h"
 
 /**
  * Version of cas_disk interface
@@ -54,7 +55,7 @@ struct casdsk_exp_obj_ops {
 	 * @brief queue_rq_fn of exported object (top) block device.
 	 * Called by cas_disk when cas_disk device is in attached mode.
 	 */
-	int (*queue_rq_fn)(struct casdsk_disk *dsk, struct request *rq,
+	CAS_BLK_STATUS_T (*queue_rq_fn)(struct casdsk_disk *dsk, struct request *rq,
 			   void *private);
 
 	/**

modules/cas_disk/exp_obj.c

@@ -91,7 +91,7 @@ CAS_DECLARE_BLOCK_CALLBACK(_casdsk_exp_obj_bio_pt_io, struct bio *bio,
 	io = bio->bi_private;
 	BUG_ON(!io);
 	CAS_BIO_ENDIO(io->bio, CAS_BIO_BISIZE(io->bio),
-			CAS_BLOCK_CALLBACK_ERROR(bio, error));
+			CAS_BLOCK_CALLBACK_ERROR(bio, CAS_ERRNO_TO_BLK_STS(error)));
 
 	if (atomic_dec_return(&io->dsk->exp_obj->pt_ios) < 0)
 		BUG();
@@ -110,14 +110,14 @@ static inline void _casdsk_exp_obj_handle_bio_pt(struct casdsk_disk *dsk,
 
 	io = kmem_cache_zalloc(casdsk_module->pt_io_ctx_cache, GFP_ATOMIC);
 	if (!io) {
-		CAS_BIO_ENDIO(bio, CAS_BIO_BISIZE(bio), -ENOMEM);
+		CAS_BIO_ENDIO(bio, CAS_BIO_BISIZE(bio), CAS_ERRNO_TO_BLK_STS(-ENOMEM));
 		return;
 	}
 
 	cloned_bio = cas_bio_clone(bio, GFP_ATOMIC);
 	if (!cloned_bio) {
 		kmem_cache_free(casdsk_module->pt_io_ctx_cache, io);
-		CAS_BIO_ENDIO(bio, CAS_BIO_BISIZE(bio), -ENOMEM);
+		CAS_BIO_ENDIO(bio, CAS_BIO_BISIZE(bio), CAS_ERRNO_TO_BLK_STS(-ENOMEM));
 		return;
 	}
 
@@ -141,7 +141,7 @@ static inline void _casdsk_exp_obj_handle_bio(struct casdsk_disk *dsk,
 	else if (casdsk_disk_is_pt(dsk))
 		_casdsk_exp_obj_handle_bio_pt(dsk, q, bio);
 	else if (casdsk_disk_is_shutdown(dsk))
-		CAS_BIO_ENDIO(bio, CAS_BIO_BISIZE(bio), -EIO);
+		CAS_BIO_ENDIO(bio, CAS_BIO_BISIZE(bio), CAS_ERRNO_TO_BLK_STS(-EIO));
 	else
 		BUG();
 }
@@ -434,7 +434,7 @@ static CAS_BLK_STATUS_T _casdsk_exp_obj_queue_qr(struct blk_mq_hw_ctx *hctx,
 	struct casdsk_disk *dsk = hctx->driver_data;
 	struct casdsk_exp_obj *exp_obj = dsk->exp_obj;
 	struct request *rq = bd->rq;
-	int result = 0;
+	CAS_BLK_STATUS_T result = CAS_BLK_STS_OK;
 
 	if (likely(exp_obj->ops && exp_obj->ops->queue_rq_fn)) {
 		exp_obj->ops->pending_rq_inc(dsk, dsk->private);