Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

6 files changed, 4170 insertions, 0 deletions

diff --git a/drivers/ntb/test/Kconfig b/drivers/ntb/test/Kconfig
new file mode 100644
index 000000000..516b991f3
--- /dev/null
+++ b/drivers/ntb/test/Kconfig
@@ -0,0 +1,37 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config NTB_PINGPONG
+	tristate "NTB Ping Pong Test Client"
+	help
+	 This is a simple ping pong driver that exercises the scratchpads and
+	 doorbells of the ntb hardware.  This driver may be used to test that
+	 your ntb hardware and drivers are functioning at a basic level.
+
+	 If unsure, say N.
+
+config NTB_TOOL
+	tristate "NTB Debugging Tool Test Client"
+	help
+	 This is a simple debugging driver that enables the doorbell and
+	 scratchpad registers to be read and written from the debugfs.  This
+	 enables more complicated debugging to be scripted from user space.
+	 This driver may be used to test that your ntb hardware and drivers are
+	 functioning at a basic level.
+
+	 If unsure, say N.
+
+config NTB_PERF
+	tristate "NTB RAW Perf Measuring Tool"
+	help
+	 This is a tool to measure raw NTB performance by transferring data
+	 to and from the window without additional software interaction.
+
+	 If unsure, say N.
+
+config NTB_MSI_TEST
+	tristate "NTB MSI Test Client"
+	depends on NTB_MSI
+	help
+	  This tool demonstrates the use of the NTB MSI library to
+	  send MSI interrupts between peers.
+
+	  If unsure, say N.
diff --git a/drivers/ntb/test/Makefile b/drivers/ntb/test/Makefile
new file mode 100644
index 000000000..19ed91d8a
--- /dev/null
+++ b/drivers/ntb/test/Makefile
@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0-only
+obj-$(CONFIG_NTB_PINGPONG) += ntb_pingpong.o
+obj-$(CONFIG_NTB_TOOL) += ntb_tool.o
+obj-$(CONFIG_NTB_PERF) += ntb_perf.o
+obj-$(CONFIG_NTB_MSI_TEST) += ntb_msi_test.o
diff --git a/drivers/ntb/test/ntb_msi_test.c b/drivers/ntb/test/ntb_msi_test.c
new file mode 100644
index 000000000..4e18e0877
--- /dev/null
+++ b/drivers/ntb/test/ntb_msi_test.c
@@ -0,0 +1,432 @@
+// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
+
+#include <linux/module.h>
+#include <linux/debugfs.h>
+#include <linux/ntb.h>
+#include <linux/pci.h>
+#include <linux/radix-tree.h>
+#include <linux/workqueue.h>
+
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_VERSION("0.1");
+MODULE_AUTHOR("Logan Gunthorpe <logang@deltatee.com>");
+MODULE_DESCRIPTION("Test for sending MSI interrupts over an NTB memory window");
+
+static int num_irqs = 4;
+module_param(num_irqs, int, 0644);
+MODULE_PARM_DESC(num_irqs, "number of irqs to use");
+
+struct ntb_msit_ctx {
+	struct ntb_dev *ntb;
+	struct dentry *dbgfs_dir;
+	struct work_struct setup_work;
+
+	struct ntb_msit_isr_ctx {
+		int irq_idx;
+		int irq_num;
+		int occurrences;
+		struct ntb_msit_ctx *nm;
+		struct ntb_msi_desc desc;
+	} *isr_ctx;
+
+	struct ntb_msit_peer {
+		struct ntb_msit_ctx *nm;
+		int pidx;
+		int num_irqs;
+		struct completion init_comp;
+		struct ntb_msi_desc *msi_desc;
+	} peers[];
+};
+
+static struct dentry *ntb_msit_dbgfs_topdir;
+
+static irqreturn_t ntb_msit_isr(int irq, void *dev)
+{
+	struct ntb_msit_isr_ctx *isr_ctx = dev;
+	struct ntb_msit_ctx *nm = isr_ctx->nm;
+
+	dev_dbg(&nm->ntb->dev, "Interrupt Occurred: %d",
+		isr_ctx->irq_idx);
+
+	isr_ctx->occurrences++;
+
+	return IRQ_HANDLED;
+}
+
+static void ntb_msit_setup_work(struct work_struct *work)
+{
+	struct ntb_msit_ctx *nm = container_of(work, struct ntb_msit_ctx,
+					       setup_work);
+	int irq_count = 0;
+	int irq;
+	int ret;
+	uintptr_t i;
+
+	ret = ntb_msi_setup_mws(nm->ntb);
+	if (ret) {
+		dev_err(&nm->ntb->dev, "Unable to setup MSI windows: %d\n",
+			ret);
+		return;
+	}
+
+	for (i = 0; i < num_irqs; i++) {
+		nm->isr_ctx[i].irq_idx = i;
+		nm->isr_ctx[i].nm = nm;
+
+		if (!nm->isr_ctx[i].irq_num) {
+			irq = ntbm_msi_request_irq(nm->ntb, ntb_msit_isr,
+						   KBUILD_MODNAME,
+						   &nm->isr_ctx[i],
+						   &nm->isr_ctx[i].desc);
+			if (irq < 0)
+				break;
+
+			nm->isr_ctx[i].irq_num = irq;
+		}
+
+		ret = ntb_spad_write(nm->ntb, 2 * i + 1,
+				     nm->isr_ctx[i].desc.addr_offset);
+		if (ret)
+			break;
+
+		ret = ntb_spad_write(nm->ntb, 2 * i + 2,
+				     nm->isr_ctx[i].desc.data);
+		if (ret)
+			break;
+
+		irq_count++;
+	}
+
+	ntb_spad_write(nm->ntb, 0, irq_count);
+	ntb_peer_db_set(nm->ntb, BIT(ntb_port_number(nm->ntb)));
+}
+
+static void ntb_msit_desc_changed(void *ctx)
+{
+	struct ntb_msit_ctx *nm = ctx;
+	int i;
+
+	dev_dbg(&nm->ntb->dev, "MSI Descriptors Changed\n");
+
+	for (i = 0; i < num_irqs; i++) {
+		ntb_spad_write(nm->ntb, 2 * i + 1,
+			       nm->isr_ctx[i].desc.addr_offset);
+		ntb_spad_write(nm->ntb, 2 * i + 2,
+			       nm->isr_ctx[i].desc.data);
+	}
+
+	ntb_peer_db_set(nm->ntb, BIT(ntb_port_number(nm->ntb)));
+}
+
+static void ntb_msit_link_event(void *ctx)
+{
+	struct ntb_msit_ctx *nm = ctx;
+
+	if (!ntb_link_is_up(nm->ntb, NULL, NULL))
+		return;
+
+	schedule_work(&nm->setup_work);
+}
+
+static void ntb_msit_copy_peer_desc(struct ntb_msit_ctx *nm, int peer)
+{
+	int i;
+	struct ntb_msi_desc *desc = nm->peers[peer].msi_desc;
+	int irq_count = nm->peers[peer].num_irqs;
+
+	for (i = 0; i < irq_count; i++) {
+		desc[i].addr_offset = ntb_peer_spad_read(nm->ntb, peer,
+							 2 * i + 1);
+		desc[i].data = ntb_peer_spad_read(nm->ntb, peer, 2 * i + 2);
+	}
+
+	dev_info(&nm->ntb->dev, "Found %d interrupts on peer %d\n",
+		 irq_count, peer);
+
+	complete_all(&nm->peers[peer].init_comp);
+}
+
+static void ntb_msit_db_event(void *ctx, int vec)
+{
+	struct ntb_msit_ctx *nm = ctx;
+	struct ntb_msi_desc *desc;
+	u64 peer_mask = ntb_db_read(nm->ntb);
+	u32 irq_count;
+	int peer;
+
+	ntb_db_clear(nm->ntb, peer_mask);
+
+	for (peer = 0; peer < sizeof(peer_mask) * 8; peer++) {
+		if (!(peer_mask & BIT(peer)))
+			continue;
+
+		irq_count = ntb_peer_spad_read(nm->ntb, peer, 0);
+		if (irq_count == -1)
+			continue;
+
+		desc = kcalloc(irq_count, sizeof(*desc), GFP_ATOMIC);
+		if (!desc)
+			continue;
+
+		kfree(nm->peers[peer].msi_desc);
+		nm->peers[peer].msi_desc = desc;
+		nm->peers[peer].num_irqs = irq_count;
+
+		ntb_msit_copy_peer_desc(nm, peer);
+	}
+}
+
+static const struct ntb_ctx_ops ntb_msit_ops = {
+	.link_event = ntb_msit_link_event,
+	.db_event = ntb_msit_db_event,
+};
+
+static int ntb_msit_dbgfs_trigger(void *data, u64 idx)
+{
+	struct ntb_msit_peer *peer = data;
+
+	if (idx >= peer->num_irqs)
+		return -EINVAL;
+
+	dev_dbg(&peer->nm->ntb->dev, "trigger irq %llu on peer %u\n",
+		idx, peer->pidx);
+
+	return ntb_msi_peer_trigger(peer->nm->ntb, peer->pidx,
+				    &peer->msi_desc[idx]);
+}
+
+DEFINE_DEBUGFS_ATTRIBUTE(ntb_msit_trigger_fops, NULL,
+			 ntb_msit_dbgfs_trigger, "%llu\n");
+
+static int ntb_msit_dbgfs_port_get(void *data, u64 *port)
+{
+	struct ntb_msit_peer *peer = data;
+
+	*port = ntb_peer_port_number(peer->nm->ntb, peer->pidx);
+
+	return 0;
+}
+
+DEFINE_DEBUGFS_ATTRIBUTE(ntb_msit_port_fops, ntb_msit_dbgfs_port_get,
+			 NULL, "%llu\n");
+
+static int ntb_msit_dbgfs_count_get(void *data, u64 *count)
+{
+	struct ntb_msit_peer *peer = data;
+
+	*count = peer->num_irqs;
+
+	return 0;
+}
+
+DEFINE_DEBUGFS_ATTRIBUTE(ntb_msit_count_fops, ntb_msit_dbgfs_count_get,
+			 NULL, "%llu\n");
+
+static int ntb_msit_dbgfs_ready_get(void *data, u64 *ready)
+{
+	struct ntb_msit_peer *peer = data;
+
+	*ready = try_wait_for_completion(&peer->init_comp);
+
+	return 0;
+}
+
+static int ntb_msit_dbgfs_ready_set(void *data, u64 ready)
+{
+	struct ntb_msit_peer *peer = data;
+
+	return wait_for_completion_interruptible(&peer->init_comp);
+}
+
+DEFINE_DEBUGFS_ATTRIBUTE(ntb_msit_ready_fops, ntb_msit_dbgfs_ready_get,
+			 ntb_msit_dbgfs_ready_set, "%llu\n");
+
+static int ntb_msit_dbgfs_occurrences_get(void *data, u64 *occurrences)
+{
+	struct ntb_msit_isr_ctx *isr_ctx = data;
+
+	*occurrences = isr_ctx->occurrences;
+
+	return 0;
+}
+
+DEFINE_DEBUGFS_ATTRIBUTE(ntb_msit_occurrences_fops,
+			 ntb_msit_dbgfs_occurrences_get,
+			 NULL, "%llu\n");
+
+static int ntb_msit_dbgfs_local_port_get(void *data, u64 *port)
+{
+	struct ntb_msit_ctx *nm = data;
+
+	*port = ntb_port_number(nm->ntb);
+
+	return 0;
+}
+
+DEFINE_DEBUGFS_ATTRIBUTE(ntb_msit_local_port_fops,
+			 ntb_msit_dbgfs_local_port_get,
+			 NULL, "%llu\n");
+
+static void ntb_msit_create_dbgfs(struct ntb_msit_ctx *nm)
+{
+	struct pci_dev *pdev = nm->ntb->pdev;
+	char buf[32];
+	int i;
+	struct dentry *peer_dir;
+
+	nm->dbgfs_dir = debugfs_create_dir(pci_name(pdev),
+					   ntb_msit_dbgfs_topdir);
+	debugfs_create_file("port", 0400, nm->dbgfs_dir, nm,
+			    &ntb_msit_local_port_fops);
+
+	for (i = 0; i < ntb_peer_port_count(nm->ntb); i++) {
+		nm->peers[i].pidx = i;
+		nm->peers[i].nm = nm;
+		init_completion(&nm->peers[i].init_comp);
+
+		snprintf(buf, sizeof(buf), "peer%d", i);
+		peer_dir = debugfs_create_dir(buf, nm->dbgfs_dir);
+
+		debugfs_create_file_unsafe("trigger", 0200, peer_dir,
+					   &nm->peers[i],
+					   &ntb_msit_trigger_fops);
+
+		debugfs_create_file_unsafe("port", 0400, peer_dir,
+					   &nm->peers[i], &ntb_msit_port_fops);
+
+		debugfs_create_file_unsafe("count", 0400, peer_dir,
+					   &nm->peers[i],
+					   &ntb_msit_count_fops);
+
+		debugfs_create_file_unsafe("ready", 0600, peer_dir,
+					   &nm->peers[i],
+					   &ntb_msit_ready_fops);
+	}
+
+	for (i = 0; i < num_irqs; i++) {
+		snprintf(buf, sizeof(buf), "irq%d_occurrences", i);
+		debugfs_create_file_unsafe(buf, 0400, nm->dbgfs_dir,
+					   &nm->isr_ctx[i],
+					   &ntb_msit_occurrences_fops);
+	}
+}
+
+static void ntb_msit_remove_dbgfs(struct ntb_msit_ctx *nm)
+{
+	debugfs_remove_recursive(nm->dbgfs_dir);
+}
+
+static int ntb_msit_probe(struct ntb_client *client, struct ntb_dev *ntb)
+{
+	struct ntb_msit_ctx *nm;
+	int peers;
+	int ret;
+
+	peers = ntb_peer_port_count(ntb);
+	if (peers <= 0)
+		return -EINVAL;
+
+	if (ntb_spad_is_unsafe(ntb) || ntb_spad_count(ntb) < 2 * num_irqs + 1) {
+		dev_err(&ntb->dev, "NTB MSI test requires at least %d spads for %d irqs\n",
+			2 * num_irqs + 1, num_irqs);
+		return -EFAULT;
+	}
+
+	ret = ntb_spad_write(ntb, 0, -1);
+	if (ret) {
+		dev_err(&ntb->dev, "Unable to write spads: %d\n", ret);
+		return ret;
+	}
+
+	ret = ntb_db_clear_mask(ntb, GENMASK(peers - 1, 0));
+	if (ret) {
+		dev_err(&ntb->dev, "Unable to clear doorbell mask: %d\n", ret);
+		return ret;
+	}
+
+	ret = ntb_msi_init(ntb, ntb_msit_desc_changed);
+	if (ret) {
+		dev_err(&ntb->dev, "Unable to initialize MSI library: %d\n",
+			ret);
+		return ret;
+	}
+
+	nm = devm_kzalloc(&ntb->dev, struct_size(nm, peers, peers), GFP_KERNEL);
+	if (!nm)
+		return -ENOMEM;
+
+	nm->isr_ctx = devm_kcalloc(&ntb->dev, num_irqs, sizeof(*nm->isr_ctx),
+				   GFP_KERNEL);
+	if (!nm->isr_ctx)
+		return -ENOMEM;
+
+	INIT_WORK(&nm->setup_work, ntb_msit_setup_work);
+	nm->ntb = ntb;
+
+	ntb_msit_create_dbgfs(nm);
+
+	ret = ntb_set_ctx(ntb, nm, &ntb_msit_ops);
+	if (ret)
+		goto remove_dbgfs;
+
+	if (!nm->isr_ctx) {
+		ret = -ENOMEM;
+		goto remove_dbgfs;
+	}
+
+	ntb_link_enable(ntb, NTB_SPEED_AUTO, NTB_WIDTH_AUTO);
+
+	return 0;
+
+remove_dbgfs:
+	ntb_msit_remove_dbgfs(nm);
+	devm_kfree(&ntb->dev, nm->isr_ctx);
+	devm_kfree(&ntb->dev, nm);
+	return ret;
+}
+
+static void ntb_msit_remove(struct ntb_client *client, struct ntb_dev *ntb)
+{
+	struct ntb_msit_ctx *nm = ntb->ctx;
+	int i;
+
+	ntb_link_disable(ntb);
+	ntb_db_set_mask(ntb, ntb_db_valid_mask(ntb));
+	ntb_msi_clear_mws(ntb);
+
+	for (i = 0; i < ntb_peer_port_count(ntb); i++)
+		kfree(nm->peers[i].msi_desc);
+
+	ntb_clear_ctx(ntb);
+	ntb_msit_remove_dbgfs(nm);
+}
+
+static struct ntb_client ntb_msit_client = {
+	.ops = {
+		.probe = ntb_msit_probe,
+		.remove = ntb_msit_remove
+	}
+};
+
+static int __init ntb_msit_init(void)
+{
+	int ret;
+
+	if (debugfs_initialized())
+		ntb_msit_dbgfs_topdir = debugfs_create_dir(KBUILD_MODNAME,
+							   NULL);
+
+	ret = ntb_register_client(&ntb_msit_client);
+	if (ret)
+		debugfs_remove_recursive(ntb_msit_dbgfs_topdir);
+
+	return ret;
+}
+module_init(ntb_msit_init);
+
+static void __exit ntb_msit_exit(void)
+{
+	ntb_unregister_client(&ntb_msit_client);
+	debugfs_remove_recursive(ntb_msit_dbgfs_topdir);
+}
+module_exit(ntb_msit_exit);
diff --git a/drivers/ntb/test/ntb_perf.c b/drivers/ntb/test/ntb_perf.c
new file mode 100644
index 000000000..65e1e5cf1
--- /dev/null
+++ b/drivers/ntb/test/ntb_perf.c
@@ -0,0 +1,1567 @@
+/*
+ * This file is provided under a dual BSD/GPLv2 license.  When using or
+ *   redistributing this file, you may do so under either license.
+ *
+ *   GPL LICENSE SUMMARY
+ *
+ *   Copyright(c) 2015 Intel Corporation. All rights reserved.
+ *   Copyright(c) 2017 T-Platforms. All Rights Reserved.
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of version 2 of the GNU General Public License as
+ *   published by the Free Software Foundation.
+ *
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2015 Intel Corporation. All rights reserved.
+ *   Copyright(c) 2017 T-Platforms. All Rights Reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copy
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * PCIe NTB Perf Linux driver
+ */
+
+/*
+ * How to use this tool, by example.
+ *
+ * Assuming $DBG_DIR is something like:
+ * '/sys/kernel/debug/ntb_perf/0000:00:03.0'
+ * Suppose aside from local device there is at least one remote device
+ * connected to NTB with index 0.
+ *-----------------------------------------------------------------------------
+ * Eg: install driver with specified chunk/total orders and dma-enabled flag
+ *
+ * root@self# insmod ntb_perf.ko chunk_order=19 total_order=28 use_dma
+ *-----------------------------------------------------------------------------
+ * Eg: check NTB ports (index) and MW mapping information
+ *
+ * root@self# cat $DBG_DIR/info
+ *-----------------------------------------------------------------------------
+ * Eg: start performance test with peer (index 0) and get the test metrics
+ *
+ * root@self# echo 0 > $DBG_DIR/run
+ * root@self# cat $DBG_DIR/run
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/pci.h>
+#include <linux/ktime.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/sizes.h>
+#include <linux/workqueue.h>
+#include <linux/debugfs.h>
+#include <linux/random.h>
+#include <linux/ntb.h>
+
+#define DRIVER_NAME		"ntb_perf"
+#define DRIVER_VERSION		"2.0"
+
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_AUTHOR("Dave Jiang <dave.jiang@intel.com>");
+MODULE_DESCRIPTION("PCIe NTB Performance Measurement Tool");
+
+#define MAX_THREADS_CNT		32
+#define DEF_THREADS_CNT		1
+#define MAX_CHUNK_SIZE		SZ_1M
+#define MAX_CHUNK_ORDER		20 /* no larger than 1M */
+
+#define DMA_TRIES		100
+#define DMA_MDELAY		10
+
+#define MSG_TRIES		1000
+#define MSG_UDELAY_LOW		1000000
+#define MSG_UDELAY_HIGH		2000000
+
+#define PERF_BUF_LEN 1024
+
+static unsigned long max_mw_size;
+module_param(max_mw_size, ulong, 0644);
+MODULE_PARM_DESC(max_mw_size, "Upper limit of memory window size");
+
+static unsigned char chunk_order = 19; /* 512K */
+module_param(chunk_order, byte, 0644);
+MODULE_PARM_DESC(chunk_order, "Data chunk order [2^n] to transfer");
+
+static unsigned char total_order = 30; /* 1G */
+module_param(total_order, byte, 0644);
+MODULE_PARM_DESC(total_order, "Total data order [2^n] to transfer");
+
+static bool use_dma; /* default to 0 */
+module_param(use_dma, bool, 0644);
+MODULE_PARM_DESC(use_dma, "Use DMA engine to measure performance");
+
+/*==============================================================================
+ *                         Perf driver data definition
+ *==============================================================================
+ */
+
+enum perf_cmd {
+	PERF_CMD_INVAL = -1,/* invalid spad command */
+	PERF_CMD_SSIZE = 0, /* send out buffer size */
+	PERF_CMD_RSIZE = 1, /* recv in  buffer size */
+	PERF_CMD_SXLAT = 2, /* send in  buffer xlat */
+	PERF_CMD_RXLAT = 3, /* recv out buffer xlat */
+	PERF_CMD_CLEAR = 4, /* clear allocated memory */
+	PERF_STS_DONE  = 5, /* init is done */
+	PERF_STS_LNKUP = 6, /* link up state flag */
+};
+
+struct perf_ctx;
+
+struct perf_peer {
+	struct perf_ctx	*perf;
+	int pidx;
+	int gidx;
+
+	/* Outbound MW params */
+	u64 outbuf_xlat;
+	resource_size_t outbuf_size;
+	void __iomem *outbuf;
+	phys_addr_t out_phys_addr;
+	dma_addr_t dma_dst_addr;
+	/* Inbound MW params */
+	dma_addr_t inbuf_xlat;
+	resource_size_t inbuf_size;
+	void		*inbuf;
+
+	/* NTB connection setup service */
+	struct work_struct	service;
+	unsigned long		sts;
+
+	struct completion init_comp;
+};
+#define to_peer_service(__work) \
+	container_of(__work, struct perf_peer, service)
+
+struct perf_thread {
+	struct perf_ctx *perf;
+	int tidx;
+
+	/* DMA-based test sync parameters */
+	atomic_t dma_sync;
+	wait_queue_head_t dma_wait;
+	struct dma_chan *dma_chan;
+
+	/* Data source and measured statistics */
+	void *src;
+	u64 copied;
+	ktime_t duration;
+	int status;
+	struct work_struct work;
+};
+#define to_thread_work(__work) \
+	container_of(__work, struct perf_thread, work)
+
+struct perf_ctx {
+	struct ntb_dev *ntb;
+
+	/* Global device index and peers descriptors */
+	int gidx;
+	int pcnt;
+	struct perf_peer *peers;
+
+	/* Performance measuring work-threads interface */
+	unsigned long busy_flag;
+	wait_queue_head_t twait;
+	atomic_t tsync;
+	u8 tcnt;
+	struct perf_peer *test_peer;
+	struct perf_thread threads[MAX_THREADS_CNT];
+
+	/* Scratchpad/Message IO operations */
+	int (*cmd_send)(struct perf_peer *peer, enum perf_cmd cmd, u64 data);
+	int (*cmd_recv)(struct perf_ctx *perf, int *pidx, enum perf_cmd *cmd,
+			u64 *data);
+
+	struct dentry *dbgfs_dir;
+};
+
+/*
+ * Scratchpads-base commands interface
+ */
+#define PERF_SPAD_CNT(_pcnt) \
+	(3*((_pcnt) + 1))
+#define PERF_SPAD_CMD(_gidx) \
+	(3*(_gidx))
+#define PERF_SPAD_LDATA(_gidx) \
+	(3*(_gidx) + 1)
+#define PERF_SPAD_HDATA(_gidx) \
+	(3*(_gidx) + 2)
+#define PERF_SPAD_NOTIFY(_gidx) \
+	(BIT_ULL(_gidx))
+
+/*
+ * Messages-base commands interface
+ */
+#define PERF_MSG_CNT		3
+#define PERF_MSG_CMD		0
+#define PERF_MSG_LDATA		1
+#define PERF_MSG_HDATA		2
+
+/*==============================================================================
+ *                           Static data declarations
+ *==============================================================================
+ */
+
+static struct dentry *perf_dbgfs_topdir;
+
+static struct workqueue_struct *perf_wq __read_mostly;
+
+/*==============================================================================
+ *                  NTB cross-link commands execution service
+ *==============================================================================
+ */
+
+static void perf_terminate_test(struct perf_ctx *perf);
+
+static inline bool perf_link_is_up(struct perf_peer *peer)
+{
+	u64 link;
+
+	link = ntb_link_is_up(peer->perf->ntb, NULL, NULL);
+	return !!(link & BIT_ULL_MASK(peer->pidx));
+}
+
+static int perf_spad_cmd_send(struct perf_peer *peer, enum perf_cmd cmd,
+			      u64 data)
+{
+	struct perf_ctx *perf = peer->perf;
+	int try;
+	u32 sts;
+
+	dev_dbg(&perf->ntb->dev, "CMD send: %d 0x%llx\n", cmd, data);
+
+	/*
+	 * Perform predefined number of attempts before give up.
+	 * We are sending the data to the port specific scratchpad, so
+	 * to prevent a multi-port access race-condition. Additionally
+	 * there is no need in local locking since only thread-safe
+	 * service work is using this method.
+	 */
+	for (try = 0; try < MSG_TRIES; try++) {
+		if (!perf_link_is_up(peer))
+			return -ENOLINK;
+
+		sts = ntb_peer_spad_read(perf->ntb, peer->pidx,
+					 PERF_SPAD_CMD(perf->gidx));
+		if (sts != PERF_CMD_INVAL) {
+			usleep_range(MSG_UDELAY_LOW, MSG_UDELAY_HIGH);
+			continue;
+		}
+
+		ntb_peer_spad_write(perf->ntb, peer->pidx,
+				    PERF_SPAD_LDATA(perf->gidx),
+				    lower_32_bits(data));
+		ntb_peer_spad_write(perf->ntb, peer->pidx,
+				    PERF_SPAD_HDATA(perf->gidx),
+				    upper_32_bits(data));
+		ntb_peer_spad_write(perf->ntb, peer->pidx,
+				    PERF_SPAD_CMD(perf->gidx),
+				    cmd);
+		ntb_peer_db_set(perf->ntb, PERF_SPAD_NOTIFY(peer->gidx));
+
+		dev_dbg(&perf->ntb->dev, "DB ring peer %#llx\n",
+			PERF_SPAD_NOTIFY(peer->gidx));
+
+		break;
+	}
+
+	return try < MSG_TRIES ? 0 : -EAGAIN;
+}
+
+static int perf_spad_cmd_recv(struct perf_ctx *perf, int *pidx,
+			      enum perf_cmd *cmd, u64 *data)
+{
+	struct perf_peer *peer;
+	u32 val;
+
+	ntb_db_clear(perf->ntb, PERF_SPAD_NOTIFY(perf->gidx));
+
+	/*
+	 * We start scanning all over, since cleared DB may have been set
+	 * by any peer. Yes, it makes peer with smaller index being
+	 * serviced with greater priority, but it's convenient for spad
+	 * and message code unification and simplicity.
+	 */
+	for (*pidx = 0; *pidx < perf->pcnt; (*pidx)++) {
+		peer = &perf->peers[*pidx];
+
+		if (!perf_link_is_up(peer))
+			continue;
+
+		val = ntb_spad_read(perf->ntb, PERF_SPAD_CMD(peer->gidx));
+		if (val == PERF_CMD_INVAL)
+			continue;
+
+		*cmd = val;
+
+		val = ntb_spad_read(perf->ntb, PERF_SPAD_LDATA(peer->gidx));
+		*data = val;
+
+		val = ntb_spad_read(perf->ntb, PERF_SPAD_HDATA(peer->gidx));
+		*data |= (u64)val << 32;
+
+		/* Next command can be retrieved from now */
+		ntb_spad_write(perf->ntb, PERF_SPAD_CMD(peer->gidx),
+			       PERF_CMD_INVAL);
+
+		dev_dbg(&perf->ntb->dev, "CMD recv: %d 0x%llx\n", *cmd, *data);
+
+		return 0;
+	}
+
+	return -ENODATA;
+}
+
+static int perf_msg_cmd_send(struct perf_peer *peer, enum perf_cmd cmd,
+			     u64 data)
+{
+	struct perf_ctx *perf = peer->perf;
+	int try, ret;
+	u64 outbits;
+
+	dev_dbg(&perf->ntb->dev, "CMD send: %d 0x%llx\n", cmd, data);
+
+	/*
+	 * Perform predefined number of attempts before give up. Message
+	 * registers are free of race-condition problem when accessed
+	 * from different ports, so we don't need splitting registers
+	 * by global device index. We also won't have local locking,
+	 * since the method is used from service work only.
+	 */
+	outbits = ntb_msg_outbits(perf->ntb);
+	for (try = 0; try < MSG_TRIES; try++) {
+		if (!perf_link_is_up(peer))
+			return -ENOLINK;
+
+		ret = ntb_msg_clear_sts(perf->ntb, outbits);
+		if (ret)
+			return ret;
+
+		ntb_peer_msg_write(perf->ntb, peer->pidx, PERF_MSG_LDATA,
+				   lower_32_bits(data));
+
+		if (ntb_msg_read_sts(perf->ntb) & outbits) {
+			usleep_range(MSG_UDELAY_LOW, MSG_UDELAY_HIGH);
+			continue;
+		}
+
+		ntb_peer_msg_write(perf->ntb, peer->pidx, PERF_MSG_HDATA,
+				   upper_32_bits(data));
+
+		/* This call shall trigger peer message event */
+		ntb_peer_msg_write(perf->ntb, peer->pidx, PERF_MSG_CMD, cmd);
+
+		break;
+	}
+
+	return try < MSG_TRIES ? 0 : -EAGAIN;
+}
+
+static int perf_msg_cmd_recv(struct perf_ctx *perf, int *pidx,
+			     enum perf_cmd *cmd, u64 *data)
+{
+	u64 inbits;
+	u32 val;
+
+	inbits = ntb_msg_inbits(perf->ntb);
+
+	if (hweight64(ntb_msg_read_sts(perf->ntb) & inbits) < 3)
+		return -ENODATA;
+
+	val = ntb_msg_read(perf->ntb, pidx, PERF_MSG_CMD);
+	*cmd = val;
+
+	val = ntb_msg_read(perf->ntb, pidx, PERF_MSG_LDATA);
+	*data = val;
+
+	val = ntb_msg_read(perf->ntb, pidx, PERF_MSG_HDATA);
+	*data |= (u64)val << 32;
+
+	/* Next command can be retrieved from now */
+	ntb_msg_clear_sts(perf->ntb, inbits);
+
+	dev_dbg(&perf->ntb->dev, "CMD recv: %d 0x%llx\n", *cmd, *data);
+
+	return 0;
+}
+
+static int perf_cmd_send(struct perf_peer *peer, enum perf_cmd cmd, u64 data)
+{
+	struct perf_ctx *perf = peer->perf;
+
+	if (cmd == PERF_CMD_SSIZE || cmd == PERF_CMD_SXLAT)
+		return perf->cmd_send(peer, cmd, data);
+
+	dev_err(&perf->ntb->dev, "Send invalid command\n");
+	return -EINVAL;
+}
+
+static int perf_cmd_exec(struct perf_peer *peer, enum perf_cmd cmd)
+{
+	switch (cmd) {
+	case PERF_CMD_SSIZE:
+	case PERF_CMD_RSIZE:
+	case PERF_CMD_SXLAT:
+	case PERF_CMD_RXLAT:
+	case PERF_CMD_CLEAR:
+		break;
+	default:
+		dev_err(&peer->perf->ntb->dev, "Exec invalid command\n");
+		return -EINVAL;
+	}
+
+	/* No need of memory barrier, since bit ops have invernal lock */
+	set_bit(cmd, &peer->sts);
+
+	dev_dbg(&peer->perf->ntb->dev, "CMD exec: %d\n", cmd);
+
+	(void)queue_work(system_highpri_wq, &peer->service);
+
+	return 0;
+}
+
+static int perf_cmd_recv(struct perf_ctx *perf)
+{
+	struct perf_peer *peer;
+	int ret, pidx, cmd;
+	u64 data;
+
+	while (!(ret = perf->cmd_recv(perf, &pidx, &cmd, &data))) {
+		peer = &perf->peers[pidx];
+
+		switch (cmd) {
+		case PERF_CMD_SSIZE:
+			peer->inbuf_size = data;
+			return perf_cmd_exec(peer, PERF_CMD_RSIZE);
+		case PERF_CMD_SXLAT:
+			peer->outbuf_xlat = data;
+			return perf_cmd_exec(peer, PERF_CMD_RXLAT);
+		default:
+			dev_err(&perf->ntb->dev, "Recv invalid command\n");
+			return -EINVAL;
+		}
+	}
+
+	/* Return 0 if no data left to process, otherwise an error */
+	return ret == -ENODATA ? 0 : ret;
+}
+
+static void perf_link_event(void *ctx)
+{
+	struct perf_ctx *perf = ctx;
+	struct perf_peer *peer;
+	bool lnk_up;
+	int pidx;
+
+	for (pidx = 0; pidx < perf->pcnt; pidx++) {
+		peer = &perf->peers[pidx];
+
+		lnk_up = perf_link_is_up(peer);
+
+		if (lnk_up &&
+		    !test_and_set_bit(PERF_STS_LNKUP, &peer->sts)) {
+			perf_cmd_exec(peer, PERF_CMD_SSIZE);
+		} else if (!lnk_up &&
+			   test_and_clear_bit(PERF_STS_LNKUP, &peer->sts)) {
+			perf_cmd_exec(peer, PERF_CMD_CLEAR);
+		}
+	}
+}
+
+static void perf_db_event(void *ctx, int vec)
+{
+	struct perf_ctx *perf = ctx;
+
+	dev_dbg(&perf->ntb->dev, "DB vec %d mask %#llx bits %#llx\n", vec,
+		ntb_db_vector_mask(perf->ntb, vec), ntb_db_read(perf->ntb));
+
+	/* Just receive all available commands */
+	(void)perf_cmd_recv(perf);
+}
+
+static void perf_msg_event(void *ctx)
+{
+	struct perf_ctx *perf = ctx;
+
+	dev_dbg(&perf->ntb->dev, "Msg status bits %#llx\n",
+		ntb_msg_read_sts(perf->ntb));
+
+	/* Messages are only sent one-by-one */
+	(void)perf_cmd_recv(perf);
+}
+
+static const struct ntb_ctx_ops perf_ops = {
+	.link_event = perf_link_event,
+	.db_event = perf_db_event,
+	.msg_event = perf_msg_event
+};
+
+static void perf_free_outbuf(struct perf_peer *peer)
+{
+	(void)ntb_peer_mw_clear_trans(peer->perf->ntb, peer->pidx, peer->gidx);
+}
+
+static int perf_setup_outbuf(struct perf_peer *peer)
+{
+	struct perf_ctx *perf = peer->perf;
+	int ret;
+
+	/* Outbuf size can be unaligned due to custom max_mw_size */
+	ret = ntb_peer_mw_set_trans(perf->ntb, peer->pidx, peer->gidx,
+				    peer->outbuf_xlat, peer->outbuf_size);
+	if (ret) {
+		dev_err(&perf->ntb->dev, "Failed to set outbuf translation\n");
+		return ret;
+	}
+
+	/* Initialization is finally done */
+	set_bit(PERF_STS_DONE, &peer->sts);
+	complete_all(&peer->init_comp);
+
+	return 0;
+}
+
+static void perf_free_inbuf(struct perf_peer *peer)
+{
+	if (!peer->inbuf)
+		return;
+
+	(void)ntb_mw_clear_trans(peer->perf->ntb, peer->pidx, peer->gidx);
+	dma_free_coherent(&peer->perf->ntb->pdev->dev, peer->inbuf_size,
+			  peer->inbuf, peer->inbuf_xlat);
+	peer->inbuf = NULL;
+}
+
+static int perf_setup_inbuf(struct perf_peer *peer)
+{
+	resource_size_t xlat_align, size_align, size_max;
+	struct perf_ctx *perf = peer->perf;
+	int ret;
+
+	/* Get inbound MW parameters */
+	ret = ntb_mw_get_align(perf->ntb, peer->pidx, perf->gidx,
+			       &xlat_align, &size_align, &size_max);
+	if (ret) {
+		dev_err(&perf->ntb->dev, "Couldn't get inbuf restrictions\n");
+		return ret;
+	}
+
+	if (peer->inbuf_size > size_max) {
+		dev_err(&perf->ntb->dev, "Too big inbuf size %pa > %pa\n",
+			&peer->inbuf_size, &size_max);
+		return -EINVAL;
+	}
+
+	peer->inbuf_size = round_up(peer->inbuf_size, size_align);
+
+	perf_free_inbuf(peer);
+
+	peer->inbuf = dma_alloc_coherent(&perf->ntb->pdev->dev,
+					 peer->inbuf_size, &peer->inbuf_xlat,
+					 GFP_KERNEL);
+	if (!peer->inbuf) {
+		dev_err(&perf->ntb->dev, "Failed to alloc inbuf of %pa\n",
+			&peer->inbuf_size);
+		return -ENOMEM;
+	}
+	if (!IS_ALIGNED(peer->inbuf_xlat, xlat_align)) {
+		ret = -EINVAL;
+		dev_err(&perf->ntb->dev, "Unaligned inbuf allocated\n");
+		goto err_free_inbuf;
+	}
+
+	ret = ntb_mw_set_trans(perf->ntb, peer->pidx, peer->gidx,
+			       peer->inbuf_xlat, peer->inbuf_size);
+	if (ret) {
+		dev_err(&perf->ntb->dev, "Failed to set inbuf translation\n");
+		goto err_free_inbuf;
+	}
+
+	/*
+	 * We submit inbuf xlat transmission cmd for execution here to follow
+	 * the code architecture, even though this method is called from service
+	 * work itself so the command will be executed right after it returns.
+	 */
+	(void)perf_cmd_exec(peer, PERF_CMD_SXLAT);
+
+	return 0;
+
+err_free_inbuf:
+	perf_free_inbuf(peer);
+
+	return ret;
+}
+
+static void perf_service_work(struct work_struct *work)
+{
+	struct perf_peer *peer = to_peer_service(work);
+
+	if (test_and_clear_bit(PERF_CMD_SSIZE, &peer->sts))
+		perf_cmd_send(peer, PERF_CMD_SSIZE, peer->outbuf_size);
+
+	if (test_and_clear_bit(PERF_CMD_RSIZE, &peer->sts))
+		perf_setup_inbuf(peer);
+
+	if (test_and_clear_bit(PERF_CMD_SXLAT, &peer->sts))
+		perf_cmd_send(peer, PERF_CMD_SXLAT, peer->inbuf_xlat);
+
+	if (test_and_clear_bit(PERF_CMD_RXLAT, &peer->sts))
+		perf_setup_outbuf(peer);
+
+	if (test_and_clear_bit(PERF_CMD_CLEAR, &peer->sts)) {
+		init_completion(&peer->init_comp);
+		clear_bit(PERF_STS_DONE, &peer->sts);
+		if (test_bit(0, &peer->perf->busy_flag) &&
+		    peer == peer->perf->test_peer) {
+			dev_warn(&peer->perf->ntb->dev,
+				"Freeing while test on-fly\n");
+			perf_terminate_test(peer->perf);
+		}
+		perf_free_outbuf(peer);
+		perf_free_inbuf(peer);
+	}
+}
+
+static int perf_init_service(struct perf_ctx *perf)
+{
+	u64 mask;
+
+	if (ntb_peer_mw_count(perf->ntb) < perf->pcnt) {
+		dev_err(&perf->ntb->dev, "Not enough memory windows\n");
+		return -EINVAL;
+	}
+
+	if (ntb_msg_count(perf->ntb) >= PERF_MSG_CNT) {
+		perf->cmd_send = perf_msg_cmd_send;
+		perf->cmd_recv = perf_msg_cmd_recv;
+
+		dev_dbg(&perf->ntb->dev, "Message service initialized\n");
+
+		return 0;
+	}
+
+	dev_dbg(&perf->ntb->dev, "Message service unsupported\n");
+
+	mask = GENMASK_ULL(perf->pcnt, 0);
+	if (ntb_spad_count(perf->ntb) >= PERF_SPAD_CNT(perf->pcnt) &&
+	    (ntb_db_valid_mask(perf->ntb) & mask) == mask) {
+		perf->cmd_send = perf_spad_cmd_send;
+		perf->cmd_recv = perf_spad_cmd_recv;
+
+		dev_dbg(&perf->ntb->dev, "Scratchpad service initialized\n");
+
+		return 0;
+	}
+
+	dev_dbg(&perf->ntb->dev, "Scratchpad service unsupported\n");
+
+	dev_err(&perf->ntb->dev, "Command services unsupported\n");
+
+	return -EINVAL;
+}
+
+static int perf_enable_service(struct perf_ctx *perf)
+{
+	u64 mask, incmd_bit;
+	int ret, sidx, scnt;
+
+	mask = ntb_db_valid_mask(perf->ntb);
+	(void)ntb_db_set_mask(perf->ntb, mask);
+
+	ret = ntb_set_ctx(perf->ntb, perf, &perf_ops);
+	if (ret)
+		return ret;
+
+	if (perf->cmd_send == perf_msg_cmd_send) {
+		u64 inbits, outbits;
+
+		inbits = ntb_msg_inbits(perf->ntb);
+		outbits = ntb_msg_outbits(perf->ntb);
+		(void)ntb_msg_set_mask(perf->ntb, inbits | outbits);
+
+		incmd_bit = BIT_ULL(__ffs64(inbits));
+		ret = ntb_msg_clear_mask(perf->ntb, incmd_bit);
+
+		dev_dbg(&perf->ntb->dev, "MSG sts unmasked %#llx\n", incmd_bit);
+	} else {
+		scnt = ntb_spad_count(perf->ntb);
+		for (sidx = 0; sidx < scnt; sidx++)
+			ntb_spad_write(perf->ntb, sidx, PERF_CMD_INVAL);
+		incmd_bit = PERF_SPAD_NOTIFY(perf->gidx);
+		ret = ntb_db_clear_mask(perf->ntb, incmd_bit);
+
+		dev_dbg(&perf->ntb->dev, "DB bits unmasked %#llx\n", incmd_bit);
+	}
+	if (ret) {
+		ntb_clear_ctx(perf->ntb);
+		return ret;
+	}
+
+	ntb_link_enable(perf->ntb, NTB_SPEED_AUTO, NTB_WIDTH_AUTO);
+	/* Might be not necessary */
+	ntb_link_event(perf->ntb);
+
+	return 0;
+}
+
+static void perf_disable_service(struct perf_ctx *perf)
+{
+	int pidx;
+
+	if (perf->cmd_send == perf_msg_cmd_send) {
+		u64 inbits;
+
+		inbits = ntb_msg_inbits(perf->ntb);
+		(void)ntb_msg_set_mask(perf->ntb, inbits);
+	} else {
+		(void)ntb_db_set_mask(perf->ntb, PERF_SPAD_NOTIFY(perf->gidx));
+	}
+
+	ntb_clear_ctx(perf->ntb);
+
+	for (pidx = 0; pidx < perf->pcnt; pidx++)
+		perf_cmd_exec(&perf->peers[pidx], PERF_CMD_CLEAR);
+
+	for (pidx = 0; pidx < perf->pcnt; pidx++)
+		flush_work(&perf->peers[pidx].service);
+
+	for (pidx = 0; pidx < perf->pcnt; pidx++) {
+		struct perf_peer *peer = &perf->peers[pidx];
+
+		ntb_spad_write(perf->ntb, PERF_SPAD_CMD(peer->gidx), 0);
+	}
+
+	ntb_db_clear(perf->ntb, PERF_SPAD_NOTIFY(perf->gidx));
+
+	ntb_link_disable(perf->ntb);
+}
+
+/*==============================================================================
+ *                      Performance measuring work-thread
+ *==============================================================================
+ */
+
+static void perf_dma_copy_callback(void *data)
+{
+	struct perf_thread *pthr = data;
+
+	atomic_dec(&pthr->dma_sync);
+	wake_up(&pthr->dma_wait);
+}
+
+static int perf_copy_chunk(struct perf_thread *pthr,
+			   void __iomem *dst, void *src, size_t len)
+{
+	struct dma_async_tx_descriptor *tx;
+	struct dmaengine_unmap_data *unmap;
+	struct device *dma_dev;
+	int try = 0, ret = 0;
+	struct perf_peer *peer = pthr->perf->test_peer;
+	void __iomem *vbase;
+	void __iomem *dst_vaddr;
+	dma_addr_t dst_dma_addr;
+
+	if (!use_dma) {
+		memcpy_toio(dst, src, len);
+		goto ret_check_tsync;
+	}
+
+	dma_dev = pthr->dma_chan->device->dev;
+
+	if (!is_dma_copy_aligned(pthr->dma_chan->device, offset_in_page(src),
+				 offset_in_page(dst), len))
+		return -EIO;
+
+	vbase = peer->outbuf;
+	dst_vaddr = dst;
+	dst_dma_addr = peer->dma_dst_addr + (dst_vaddr - vbase);
+
+	unmap = dmaengine_get_unmap_data(dma_dev, 1, GFP_NOWAIT);
+	if (!unmap)
+		return -ENOMEM;
+
+	unmap->len = len;
+	unmap->addr[0] = dma_map_page(dma_dev, virt_to_page(src),
+		offset_in_page(src), len, DMA_TO_DEVICE);
+	if (dma_mapping_error(dma_dev, unmap->addr[0])) {
+		ret = -EIO;
+		goto err_free_resource;
+	}
+	unmap->to_cnt = 1;
+
+	do {
+		tx = dmaengine_prep_dma_memcpy(pthr->dma_chan, dst_dma_addr,
+			unmap->addr[0], len, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+		if (!tx)
+			msleep(DMA_MDELAY);
+	} while (!tx && (try++ < DMA_TRIES));
+
+	if (!tx) {
+		ret = -EIO;
+		goto err_free_resource;
+	}
+
+	tx->callback = perf_dma_copy_callback;
+	tx->callback_param = pthr;
+	dma_set_unmap(tx, unmap);
+
+	ret = dma_submit_error(dmaengine_submit(tx));
+	if (ret) {
+		dmaengine_unmap_put(unmap);
+		goto err_free_resource;
+	}
+
+	dmaengine_unmap_put(unmap);
+
+	atomic_inc(&pthr->dma_sync);
+	dma_async_issue_pending(pthr->dma_chan);
+
+ret_check_tsync:
+	return likely(atomic_read(&pthr->perf->tsync) > 0) ? 0 : -EINTR;
+
+err_free_resource:
+	dmaengine_unmap_put(unmap);
+
+	return ret;
+}
+
+static bool perf_dma_filter(struct dma_chan *chan, void *data)
+{
+	struct perf_ctx *perf = data;
+	int node;
+
+	node = dev_to_node(&perf->ntb->dev);
+
+	return node == NUMA_NO_NODE || node == dev_to_node(chan->device->dev);
+}
+
+static int perf_init_test(struct perf_thread *pthr)
+{
+	struct perf_ctx *perf = pthr->perf;
+	dma_cap_mask_t dma_mask;
+	struct perf_peer *peer = pthr->perf->test_peer;
+
+	pthr->src = kmalloc_node(perf->test_peer->outbuf_size, GFP_KERNEL,
+				 dev_to_node(&perf->ntb->dev));
+	if (!pthr->src)
+		return -ENOMEM;
+
+	get_random_bytes(pthr->src, perf->test_peer->outbuf_size);
+
+	if (!use_dma)
+		return 0;
+
+	dma_cap_zero(dma_mask);
+	dma_cap_set(DMA_MEMCPY, dma_mask);
+	pthr->dma_chan = dma_request_channel(dma_mask, perf_dma_filter, perf);
+	if (!pthr->dma_chan) {
+		dev_err(&perf->ntb->dev, "%d: Failed to get DMA channel\n",
+			pthr->tidx);
+		goto err_free;
+	}
+	peer->dma_dst_addr =
+		dma_map_resource(pthr->dma_chan->device->dev,
+				 peer->out_phys_addr, peer->outbuf_size,
+				 DMA_FROM_DEVICE, 0);
+	if (dma_mapping_error(pthr->dma_chan->device->dev,
+			      peer->dma_dst_addr)) {
+		dev_err(pthr->dma_chan->device->dev, "%d: Failed to map DMA addr\n",
+			pthr->tidx);
+		peer->dma_dst_addr = 0;
+		dma_release_channel(pthr->dma_chan);
+		goto err_free;
+	}
+	dev_dbg(pthr->dma_chan->device->dev, "%d: Map MMIO %pa to DMA addr %pad\n",
+			pthr->tidx,
+			&peer->out_phys_addr,
+			&peer->dma_dst_addr);
+
+	atomic_set(&pthr->dma_sync, 0);
+	return 0;
+
+err_free:
+	atomic_dec(&perf->tsync);
+	wake_up(&perf->twait);
+	kfree(pthr->src);
+	return -ENODEV;
+}
+
+static int perf_run_test(struct perf_thread *pthr)
+{
+	struct perf_peer *peer = pthr->perf->test_peer;
+	struct perf_ctx *perf = pthr->perf;
+	void __iomem *flt_dst, *bnd_dst;
+	u64 total_size, chunk_size;
+	void *flt_src;
+	int ret = 0;
+
+	total_size = 1ULL << total_order;
+	chunk_size = 1ULL << chunk_order;
+	chunk_size = min_t(u64, peer->outbuf_size, chunk_size);
+
+	flt_src = pthr->src;
+	bnd_dst = peer->outbuf + peer->outbuf_size;
+	flt_dst = peer->outbuf;
+
+	pthr->duration = ktime_get();
+
+	/* Copied field is cleared on test launch stage */
+	while (pthr->copied < total_size) {
+		ret = perf_copy_chunk(pthr, flt_dst, flt_src, chunk_size);
+		if (ret) {
+			dev_err(&perf->ntb->dev, "%d: Got error %d on test\n",
+				pthr->tidx, ret);
+			return ret;
+		}
+
+		pthr->copied += chunk_size;
+
+		flt_dst += chunk_size;
+		flt_src += chunk_size;
+		if (flt_dst >= bnd_dst || flt_dst < peer->outbuf) {
+			flt_dst = peer->outbuf;
+			flt_src = pthr->src;
+		}
+
+		/* Give up CPU to give a chance for other threads to use it */
+		schedule();
+	}
+
+	return 0;
+}
+
+static int perf_sync_test(struct perf_thread *pthr)
+{
+	struct perf_ctx *perf = pthr->perf;
+
+	if (!use_dma)
+		goto no_dma_ret;
+
+	wait_event(pthr->dma_wait,
+		   (atomic_read(&pthr->dma_sync) == 0 ||
+		    atomic_read(&perf->tsync) < 0));
+
+	if (atomic_read(&perf->tsync) < 0)
+		return -EINTR;
+
+no_dma_ret:
+	pthr->duration = ktime_sub(ktime_get(), pthr->duration);
+
+	dev_dbg(&perf->ntb->dev, "%d: copied %llu bytes\n",
+		pthr->tidx, pthr->copied);
+
+	dev_dbg(&perf->ntb->dev, "%d: lasted %llu usecs\n",
+		pthr->tidx, ktime_to_us(pthr->duration));
+
+	dev_dbg(&perf->ntb->dev, "%d: %llu MBytes/s\n", pthr->tidx,
+		div64_u64(pthr->copied, ktime_to_us(pthr->duration)));
+
+	return 0;
+}
+
+static void perf_clear_test(struct perf_thread *pthr)
+{
+	struct perf_ctx *perf = pthr->perf;
+
+	if (!use_dma)
+		goto no_dma_notify;
+
+	/*
+	 * If test finished without errors, termination isn't needed.
+	 * We call it anyway just to be sure of the transfers completion.
+	 */
+	(void)dmaengine_terminate_sync(pthr->dma_chan);
+	if (pthr->perf->test_peer->dma_dst_addr)
+		dma_unmap_resource(pthr->dma_chan->device->dev,
+				   pthr->perf->test_peer->dma_dst_addr,
+				   pthr->perf->test_peer->outbuf_size,
+				   DMA_FROM_DEVICE, 0);
+
+	dma_release_channel(pthr->dma_chan);
+
+no_dma_notify:
+	atomic_dec(&perf->tsync);
+	wake_up(&perf->twait);
+	kfree(pthr->src);
+}
+
+static void perf_thread_work(struct work_struct *work)
+{
+	struct perf_thread *pthr = to_thread_work(work);
+	int ret;
+
+	/*
+	 * Perform stages in compliance with use_dma flag value.
+	 * Test status is changed only if error happened, otherwise
+	 * status -ENODATA is kept while test is on-fly. Results
+	 * synchronization is performed only if test fininshed
+	 * without an error or interruption.
+	 */
+	ret = perf_init_test(pthr);
+	if (ret) {
+		pthr->status = ret;
+		return;
+	}
+
+	ret = perf_run_test(pthr);
+	if (ret) {
+		pthr->status = ret;
+		goto err_clear_test;
+	}
+
+	pthr->status = perf_sync_test(pthr);
+
+err_clear_test:
+	perf_clear_test(pthr);
+}
+
+static int perf_set_tcnt(struct perf_ctx *perf, u8 tcnt)
+{
+	if (tcnt == 0 || tcnt > MAX_THREADS_CNT)
+		return -EINVAL;
+
+	if (test_and_set_bit_lock(0, &perf->busy_flag))
+		return -EBUSY;
+
+	perf->tcnt = tcnt;
+
+	clear_bit_unlock(0, &perf->busy_flag);
+
+	return 0;
+}
+
+static void perf_terminate_test(struct perf_ctx *perf)
+{
+	int tidx;
+
+	atomic_set(&perf->tsync, -1);
+	wake_up(&perf->twait);
+
+	for (tidx = 0; tidx < MAX_THREADS_CNT; tidx++) {
+		wake_up(&perf->threads[tidx].dma_wait);
+		cancel_work_sync(&perf->threads[tidx].work);
+	}
+}
+
+static int perf_submit_test(struct perf_peer *peer)
+{
+	struct perf_ctx *perf = peer->perf;
+	struct perf_thread *pthr;
+	int tidx, ret;
+
+	ret = wait_for_completion_interruptible(&peer->init_comp);
+	if (ret < 0)
+		return ret;
+
+	if (test_and_set_bit_lock(0, &perf->busy_flag))
+		return -EBUSY;
+
+	perf->test_peer = peer;
+	atomic_set(&perf->tsync, perf->tcnt);
+
+	for (tidx = 0; tidx < MAX_THREADS_CNT; tidx++) {
+		pthr = &perf->threads[tidx];
+
+		pthr->status = -ENODATA;
+		pthr->copied = 0;
+		pthr->duration = ktime_set(0, 0);
+		if (tidx < perf->tcnt)
+			(void)queue_work(perf_wq, &pthr->work);
+	}
+
+	ret = wait_event_interruptible(perf->twait,
+				       atomic_read(&perf->tsync) <= 0);
+	if (ret == -ERESTARTSYS) {
+		perf_terminate_test(perf);
+		ret = -EINTR;
+	}
+
+	clear_bit_unlock(0, &perf->busy_flag);
+
+	return ret;
+}
+
+static int perf_read_stats(struct perf_ctx *perf, char *buf,
+			   size_t size, ssize_t *pos)
+{
+	struct perf_thread *pthr;
+	int tidx;
+
+	if (test_and_set_bit_lock(0, &perf->busy_flag))
+		return -EBUSY;
+
+	(*pos) += scnprintf(buf + *pos, size - *pos,
+		"    Peer %d test statistics:\n", perf->test_peer->pidx);
+
+	for (tidx = 0; tidx < MAX_THREADS_CNT; tidx++) {
+		pthr = &perf->threads[tidx];
+
+		if (pthr->status == -ENODATA)
+			continue;
+
+		if (pthr->status) {
+			(*pos) += scnprintf(buf + *pos, size - *pos,
+				"%d: error status %d\n", tidx, pthr->status);
+			continue;
+		}
+
+		(*pos) += scnprintf(buf + *pos, size - *pos,
+			"%d: copied %llu bytes in %llu usecs, %llu MBytes/s\n",
+			tidx, pthr->copied, ktime_to_us(pthr->duration),
+			div64_u64(pthr->copied, ktime_to_us(pthr->duration)));
+	}
+
+	clear_bit_unlock(0, &perf->busy_flag);
+
+	return 0;
+}
+
+static void perf_init_threads(struct perf_ctx *perf)
+{
+	struct perf_thread *pthr;
+	int tidx;
+
+	perf->tcnt = DEF_THREADS_CNT;
+	perf->test_peer = &perf->peers[0];
+	init_waitqueue_head(&perf->twait);
+
+	for (tidx = 0; tidx < MAX_THREADS_CNT; tidx++) {
+		pthr = &perf->threads[tidx];
+
+		pthr->perf = perf;
+		pthr->tidx = tidx;
+		pthr->status = -ENODATA;
+		init_waitqueue_head(&pthr->dma_wait);
+		INIT_WORK(&pthr->work, perf_thread_work);
+	}
+}
+
+static void perf_clear_threads(struct perf_ctx *perf)
+{
+	perf_terminate_test(perf);
+}
+
+/*==============================================================================
+ *                               DebugFS nodes
+ *==============================================================================
+ */
+
+static ssize_t perf_dbgfs_read_info(struct file *filep, char __user *ubuf,
+				    size_t size, loff_t *offp)
+{
+	struct perf_ctx *perf = filep->private_data;
+	struct perf_peer *peer;
+	size_t buf_size;
+	ssize_t pos = 0;
+	int ret, pidx;
+	char *buf;
+
+	buf_size = min_t(size_t, size, 0x1000U);
+
+	buf = kmalloc(buf_size, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	pos += scnprintf(buf + pos, buf_size - pos,
+		"    Performance measuring tool info:\n\n");
+
+	pos += scnprintf(buf + pos, buf_size - pos,
+		"Local port %d, Global index %d\n", ntb_port_number(perf->ntb),
+		perf->gidx);
+	pos += scnprintf(buf + pos, buf_size - pos, "Test status: ");
+	if (test_bit(0, &perf->busy_flag)) {
+		pos += scnprintf(buf + pos, buf_size - pos,
+			"on-fly with port %d (%d)\n",
+			ntb_peer_port_number(perf->ntb, perf->test_peer->pidx),
+			perf->test_peer->pidx);
+	} else {
+		pos += scnprintf(buf + pos, buf_size - pos, "idle\n");
+	}
+
+	for (pidx = 0; pidx < perf->pcnt; pidx++) {
+		peer = &perf->peers[pidx];
+
+		pos += scnprintf(buf + pos, buf_size - pos,
+			"Port %d (%d), Global index %d:\n",
+			ntb_peer_port_number(perf->ntb, peer->pidx), peer->pidx,
+			peer->gidx);
+
+		pos += scnprintf(buf + pos, buf_size - pos,
+			"\tLink status: %s\n",
+			test_bit(PERF_STS_LNKUP, &peer->sts) ? "up" : "down");
+
+		pos += scnprintf(buf + pos, buf_size - pos,
+			"\tOut buffer addr 0x%pK\n", peer->outbuf);
+
+		pos += scnprintf(buf + pos, buf_size - pos,
+			"\tOut buff phys addr %pa[p]\n", &peer->out_phys_addr);
+
+		pos += scnprintf(buf + pos, buf_size - pos,
+			"\tOut buffer size %pa\n", &peer->outbuf_size);
+
+		pos += scnprintf(buf + pos, buf_size - pos,
+			"\tOut buffer xlat 0x%016llx[p]\n", peer->outbuf_xlat);
+
+		if (!peer->inbuf) {
+			pos += scnprintf(buf + pos, buf_size - pos,
+				"\tIn buffer addr: unallocated\n");
+			continue;
+		}
+
+		pos += scnprintf(buf + pos, buf_size - pos,
+			"\tIn buffer addr 0x%pK\n", peer->inbuf);
+
+		pos += scnprintf(buf + pos, buf_size - pos,
+			"\tIn buffer size %pa\n", &peer->inbuf_size);
+
+		pos += scnprintf(buf + pos, buf_size - pos,
+			"\tIn buffer xlat %pad[p]\n", &peer->inbuf_xlat);
+	}
+
+	ret = simple_read_from_buffer(ubuf, size, offp, buf, pos);
+	kfree(buf);
+
+	return ret;
+}
+
+static const struct file_operations perf_dbgfs_info = {
+	.open = simple_open,
+	.read = perf_dbgfs_read_info
+};
+
+static ssize_t perf_dbgfs_read_run(struct file *filep, char __user *ubuf,
+				   size_t size, loff_t *offp)
+{
+	struct perf_ctx *perf = filep->private_data;
+	ssize_t ret, pos = 0;
+	char *buf;
+
+	buf = kmalloc(PERF_BUF_LEN, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	ret = perf_read_stats(perf, buf, PERF_BUF_LEN, &pos);
+	if (ret)
+		goto err_free;
+
+	ret = simple_read_from_buffer(ubuf, size, offp, buf, pos);
+err_free:
+	kfree(buf);
+
+	return ret;
+}
+
+static ssize_t perf_dbgfs_write_run(struct file *filep, const char __user *ubuf,
+				    size_t size, loff_t *offp)
+{
+	struct perf_ctx *perf = filep->private_data;
+	struct perf_peer *peer;
+	int pidx, ret;
+
+	ret = kstrtoint_from_user(ubuf, size, 0, &pidx);
+	if (ret)
+		return ret;
+
+	if (pidx < 0 || pidx >= perf->pcnt)
+		return -EINVAL;
+
+	peer = &perf->peers[pidx];
+
+	ret = perf_submit_test(peer);
+	if (ret)
+		return ret;
+
+	return size;
+}
+
+static const struct file_operations perf_dbgfs_run = {
+	.open = simple_open,
+	.read = perf_dbgfs_read_run,
+	.write = perf_dbgfs_write_run
+};
+
+static ssize_t perf_dbgfs_read_tcnt(struct file *filep, char __user *ubuf,
+				    size_t size, loff_t *offp)
+{
+	struct perf_ctx *perf = filep->private_data;
+	char buf[8];
+	ssize_t pos;
+
+	pos = scnprintf(buf, sizeof(buf), "%hhu\n", perf->tcnt);
+
+	return simple_read_from_buffer(ubuf, size, offp, buf, pos);
+}
+
+static ssize_t perf_dbgfs_write_tcnt(struct file *filep,
+				     const char __user *ubuf,
+				     size_t size, loff_t *offp)
+{
+	struct perf_ctx *perf = filep->private_data;
+	int ret;
+	u8 val;
+
+	ret = kstrtou8_from_user(ubuf, size, 0, &val);
+	if (ret)
+		return ret;
+
+	ret = perf_set_tcnt(perf, val);
+	if (ret)
+		return ret;
+
+	return size;
+}
+
+static const struct file_operations perf_dbgfs_tcnt = {
+	.open = simple_open,
+	.read = perf_dbgfs_read_tcnt,
+	.write = perf_dbgfs_write_tcnt
+};
+
+static void perf_setup_dbgfs(struct perf_ctx *perf)
+{
+	struct pci_dev *pdev = perf->ntb->pdev;
+
+	perf->dbgfs_dir = debugfs_create_dir(pci_name(pdev), perf_dbgfs_topdir);
+	if (!perf->dbgfs_dir) {
+		dev_warn(&perf->ntb->dev, "DebugFS unsupported\n");
+		return;
+	}
+
+	debugfs_create_file("info", 0600, perf->dbgfs_dir, perf,
+			    &perf_dbgfs_info);
+
+	debugfs_create_file("run", 0600, perf->dbgfs_dir, perf,
+			    &perf_dbgfs_run);
+
+	debugfs_create_file("threads_count", 0600, perf->dbgfs_dir, perf,
+			    &perf_dbgfs_tcnt);
+
+	/* They are made read-only for test exec safety and integrity */
+	debugfs_create_u8("chunk_order", 0500, perf->dbgfs_dir, &chunk_order);
+
+	debugfs_create_u8("total_order", 0500, perf->dbgfs_dir, &total_order);
+
+	debugfs_create_bool("use_dma", 0500, perf->dbgfs_dir, &use_dma);
+}
+
+static void perf_clear_dbgfs(struct perf_ctx *perf)
+{
+	debugfs_remove_recursive(perf->dbgfs_dir);
+}
+
+/*==============================================================================
+ *                        Basic driver initialization
+ *==============================================================================
+ */
+
+static struct perf_ctx *perf_create_data(struct ntb_dev *ntb)
+{
+	struct perf_ctx *perf;
+
+	perf = devm_kzalloc(&ntb->dev, sizeof(*perf), GFP_KERNEL);
+	if (!perf)
+		return ERR_PTR(-ENOMEM);
+
+	perf->pcnt = ntb_peer_port_count(ntb);
+	perf->peers = devm_kcalloc(&ntb->dev, perf->pcnt, sizeof(*perf->peers),
+				  GFP_KERNEL);
+	if (!perf->peers)
+		return ERR_PTR(-ENOMEM);
+
+	perf->ntb = ntb;
+
+	return perf;
+}
+
+static int perf_setup_peer_mw(struct perf_peer *peer)
+{
+	struct perf_ctx *perf = peer->perf;
+	phys_addr_t phys_addr;
+	int ret;
+
+	/* Get outbound MW parameters and map it */
+	ret = ntb_peer_mw_get_addr(perf->ntb, perf->gidx, &phys_addr,
+				   &peer->outbuf_size);
+	if (ret)
+		return ret;
+
+	peer->outbuf = devm_ioremap_wc(&perf->ntb->dev, phys_addr,
+					peer->outbuf_size);
+	if (!peer->outbuf)
+		return -ENOMEM;
+
+	peer->out_phys_addr = phys_addr;
+
+	if (max_mw_size && peer->outbuf_size > max_mw_size) {
+		peer->outbuf_size = max_mw_size;
+		dev_warn(&peer->perf->ntb->dev,
+			"Peer %d outbuf reduced to %pa\n", peer->pidx,
+			&peer->outbuf_size);
+	}
+
+	return 0;
+}
+
+static int perf_init_peers(struct perf_ctx *perf)
+{
+	struct perf_peer *peer;
+	int pidx, lport, ret;
+
+	lport = ntb_port_number(perf->ntb);
+	perf->gidx = -1;
+	for (pidx = 0; pidx < perf->pcnt; pidx++) {
+		peer = &perf->peers[pidx];
+
+		peer->perf = perf;
+		peer->pidx = pidx;
+		if (lport < ntb_peer_port_number(perf->ntb, pidx)) {
+			if (perf->gidx == -1)
+				perf->gidx = pidx;
+			peer->gidx = pidx + 1;
+		} else {
+			peer->gidx = pidx;
+		}
+		INIT_WORK(&peer->service, perf_service_work);
+		init_completion(&peer->init_comp);
+	}
+	if (perf->gidx == -1)
+		perf->gidx = pidx;
+
+	/*
+	 * Hardware with only two ports may not have unique port
+	 * numbers. In this case, the gidxs should all be zero.
+	 */
+	if (perf->pcnt == 1 &&  ntb_port_number(perf->ntb) == 0 &&
+	    ntb_peer_port_number(perf->ntb, 0) == 0) {
+		perf->gidx = 0;
+		perf->peers[0].gidx = 0;
+	}
+
+	for (pidx = 0; pidx < perf->pcnt; pidx++) {
+		ret = perf_setup_peer_mw(&perf->peers[pidx]);
+		if (ret)
+			return ret;
+	}
+
+	dev_dbg(&perf->ntb->dev, "Global port index %d\n", perf->gidx);
+
+	return 0;
+}
+
+static int perf_probe(struct ntb_client *client, struct ntb_dev *ntb)
+{
+	struct perf_ctx *perf;
+	int ret;
+
+	perf = perf_create_data(ntb);
+	if (IS_ERR(perf))
+		return PTR_ERR(perf);
+
+	ret = perf_init_peers(perf);
+	if (ret)
+		return ret;
+
+	perf_init_threads(perf);
+
+	ret = perf_init_service(perf);
+	if (ret)
+		return ret;
+
+	ret = perf_enable_service(perf);
+	if (ret)
+		return ret;
+
+	perf_setup_dbgfs(perf);
+
+	return 0;
+}
+
+static void perf_remove(struct ntb_client *client, struct ntb_dev *ntb)
+{
+	struct perf_ctx *perf = ntb->ctx;
+
+	perf_clear_dbgfs(perf);
+
+	perf_disable_service(perf);
+
+	perf_clear_threads(perf);
+}
+
+static struct ntb_client perf_client = {
+	.ops = {
+		.probe = perf_probe,
+		.remove = perf_remove
+	}
+};
+
+static int __init perf_init(void)
+{
+	int ret;
+
+	if (chunk_order > MAX_CHUNK_ORDER) {
+		chunk_order = MAX_CHUNK_ORDER;
+		pr_info("Chunk order reduced to %hhu\n", chunk_order);
+	}
+
+	if (total_order < chunk_order) {
+		total_order = chunk_order;
+		pr_info("Total data order reduced to %hhu\n", total_order);
+	}
+
+	perf_wq = alloc_workqueue("perf_wq", WQ_UNBOUND | WQ_SYSFS, 0);
+	if (!perf_wq)
+		return -ENOMEM;
+
+	if (debugfs_initialized())
+		perf_dbgfs_topdir = debugfs_create_dir(KBUILD_MODNAME, NULL);
+
+	ret = ntb_register_client(&perf_client);
+	if (ret) {
+		debugfs_remove_recursive(perf_dbgfs_topdir);
+		destroy_workqueue(perf_wq);
+	}
+
+	return ret;
+}
+module_init(perf_init);
+
+static void __exit perf_exit(void)
+{
+	ntb_unregister_client(&perf_client);
+	debugfs_remove_recursive(perf_dbgfs_topdir);
+	destroy_workqueue(perf_wq);
+}
+module_exit(perf_exit);
diff --git a/drivers/ntb/test/ntb_pingpong.c b/drivers/ntb/test/ntb_pingpong.c
new file mode 100644
index 000000000..8aeca7914
--- /dev/null
+++ b/drivers/ntb/test/ntb_pingpong.c
@@ -0,0 +1,433 @@
+/*
+ *   This file is provided under a dual BSD/GPLv2 license.  When using or
+ *   redistributing this file, you may do so under either license.
+ *
+ *   GPL LICENSE SUMMARY
+ *
+ *   Copyright (C) 2015 EMC Corporation. All Rights Reserved.
+ *   Copyright (C) 2017 T-Platforms. All Rights Reserved.
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of version 2 of the GNU General Public License as
+ *   published by the Free Software Foundation.
+ *
+ *   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
+ *   General Public License for more details.
+ *
+ *   BSD LICENSE
+ *
+ *   Copyright (C) 2015 EMC Corporation. All Rights Reserved.
+ *   Copyright (C) 2017 T-Platforms. All Rights Reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copy
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * PCIe NTB Pingpong Linux driver
+ */
+
+/*
+ * How to use this tool, by example.
+ *
+ * Assuming $DBG_DIR is something like:
+ * '/sys/kernel/debug/ntb_perf/0000:00:03.0'
+ * Suppose aside from local device there is at least one remote device
+ * connected to NTB with index 0.
+ *-----------------------------------------------------------------------------
+ * Eg: install driver with specified delay between doorbell event and response
+ *
+ * root@self# insmod ntb_pingpong.ko delay_ms=1000
+ *-----------------------------------------------------------------------------
+ * Eg: get number of ping-pong cycles performed
+ *
+ * root@self# cat $DBG_DIR/count
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/bitops.h>
+
+#include <linux/pci.h>
+#include <linux/slab.h>
+#include <linux/hrtimer.h>
+#include <linux/debugfs.h>
+
+#include <linux/ntb.h>
+
+#define DRIVER_NAME		"ntb_pingpong"
+#define DRIVER_VERSION		"2.0"
+
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_AUTHOR("Allen Hubbe <Allen.Hubbe@emc.com>");
+MODULE_DESCRIPTION("PCIe NTB Simple Pingpong Client");
+
+static unsigned int unsafe;
+module_param(unsafe, uint, 0644);
+MODULE_PARM_DESC(unsafe, "Run even though ntb operations may be unsafe");
+
+static unsigned int delay_ms = 1000;
+module_param(delay_ms, uint, 0644);
+MODULE_PARM_DESC(delay_ms, "Milliseconds to delay the response to peer");
+
+struct pp_ctx {
+	struct ntb_dev *ntb;
+	struct hrtimer timer;
+	u64 in_db;
+	u64 out_db;
+	int out_pidx;
+	u64 nmask;
+	u64 pmask;
+	atomic_t count;
+	spinlock_t lock;
+	struct dentry *dbgfs_dir;
+};
+#define to_pp_timer(__timer) \
+	container_of(__timer, struct pp_ctx, timer)
+
+static struct dentry *pp_dbgfs_topdir;
+
+static int pp_find_next_peer(struct pp_ctx *pp)
+{
+	u64 link, out_db;
+	int pidx;
+
+	link = ntb_link_is_up(pp->ntb, NULL, NULL);
+
+	/* Find next available peer */
+	if (link & pp->nmask)
+		pidx = __ffs64(link & pp->nmask);
+	else if (link & pp->pmask)
+		pidx = __ffs64(link & pp->pmask);
+	else
+		return -ENODEV;
+
+	out_db = BIT_ULL(ntb_peer_port_number(pp->ntb, pidx));
+
+	spin_lock(&pp->lock);
+	pp->out_pidx = pidx;
+	pp->out_db = out_db;
+	spin_unlock(&pp->lock);
+
+	return 0;
+}
+
+static void pp_setup(struct pp_ctx *pp)
+{
+	int ret;
+
+	ntb_db_set_mask(pp->ntb, pp->in_db);
+
+	hrtimer_cancel(&pp->timer);
+
+	ret = pp_find_next_peer(pp);
+	if (ret == -ENODEV) {
+		dev_dbg(&pp->ntb->dev, "Got no peers, so cancel\n");
+		return;
+	}
+
+	dev_dbg(&pp->ntb->dev, "Ping-pong started with port %d, db %#llx\n",
+		ntb_peer_port_number(pp->ntb, pp->out_pidx), pp->out_db);
+
+	hrtimer_start(&pp->timer, ms_to_ktime(delay_ms), HRTIMER_MODE_REL);
+}
+
+static void pp_clear(struct pp_ctx *pp)
+{
+	hrtimer_cancel(&pp->timer);
+
+	ntb_db_set_mask(pp->ntb, pp->in_db);
+
+	dev_dbg(&pp->ntb->dev, "Ping-pong cancelled\n");
+}
+
+static void pp_ping(struct pp_ctx *pp)
+{
+	u32 count;
+
+	count = atomic_read(&pp->count);
+
+	spin_lock(&pp->lock);
+	ntb_peer_spad_write(pp->ntb, pp->out_pidx, 0, count);
+	ntb_peer_msg_write(pp->ntb, pp->out_pidx, 0, count);
+
+	dev_dbg(&pp->ntb->dev, "Ping port %d spad %#x, msg %#x\n",
+		ntb_peer_port_number(pp->ntb, pp->out_pidx), count, count);
+
+	ntb_peer_db_set(pp->ntb, pp->out_db);
+	ntb_db_clear_mask(pp->ntb, pp->in_db);
+	spin_unlock(&pp->lock);
+}
+
+static void pp_pong(struct pp_ctx *pp)
+{
+	u32 msg_data, spad_data;
+	int pidx = 0;
+
+	/* Read pong data */
+	spad_data = ntb_spad_read(pp->ntb, 0);
+	msg_data = ntb_msg_read(pp->ntb, &pidx, 0);
+	ntb_msg_clear_sts(pp->ntb, -1);
+
+	/*
+	 * Scratchpad and message data may differ, since message register can't
+	 * be rewritten unless status is cleared. Additionally either of them
+	 * might be unsupported
+	 */
+	dev_dbg(&pp->ntb->dev, "Pong spad %#x, msg %#x (port %d)\n",
+		spad_data, msg_data, ntb_peer_port_number(pp->ntb, pidx));
+
+	atomic_inc(&pp->count);
+
+	ntb_db_set_mask(pp->ntb, pp->in_db);
+	ntb_db_clear(pp->ntb, pp->in_db);
+
+	hrtimer_start(&pp->timer, ms_to_ktime(delay_ms), HRTIMER_MODE_REL);
+}
+
+static enum hrtimer_restart pp_timer_func(struct hrtimer *t)
+{
+	struct pp_ctx *pp = to_pp_timer(t);
+
+	pp_ping(pp);
+
+	return HRTIMER_NORESTART;
+}
+
+static void pp_link_event(void *ctx)
+{
+	struct pp_ctx *pp = ctx;
+
+	pp_setup(pp);
+}
+
+static void pp_db_event(void *ctx, int vec)
+{
+	struct pp_ctx *pp = ctx;
+
+	pp_pong(pp);
+}
+
+static const struct ntb_ctx_ops pp_ops = {
+	.link_event = pp_link_event,
+	.db_event = pp_db_event
+};
+
+static int pp_check_ntb(struct ntb_dev *ntb)
+{
+	u64 pmask;
+
+	if (ntb_db_is_unsafe(ntb)) {
+		dev_dbg(&ntb->dev, "Doorbell is unsafe\n");
+		if (!unsafe)
+			return -EINVAL;
+	}
+
+	if (ntb_spad_is_unsafe(ntb)) {
+		dev_dbg(&ntb->dev, "Scratchpad is unsafe\n");
+		if (!unsafe)
+			return -EINVAL;
+	}
+
+	pmask = GENMASK_ULL(ntb_peer_port_count(ntb), 0);
+	if ((ntb_db_valid_mask(ntb) & pmask) != pmask) {
+		dev_err(&ntb->dev, "Unsupported DB configuration\n");
+		return -EINVAL;
+	}
+
+	if (ntb_spad_count(ntb) < 1 && ntb_msg_count(ntb) < 1) {
+		dev_err(&ntb->dev, "Scratchpads and messages unsupported\n");
+		return -EINVAL;
+	} else if (ntb_spad_count(ntb) < 1) {
+		dev_dbg(&ntb->dev, "Scratchpads unsupported\n");
+	} else if (ntb_msg_count(ntb) < 1) {
+		dev_dbg(&ntb->dev, "Messages unsupported\n");
+	}
+
+	return 0;
+}
+
+static struct pp_ctx *pp_create_data(struct ntb_dev *ntb)
+{
+	struct pp_ctx *pp;
+
+	pp = devm_kzalloc(&ntb->dev, sizeof(*pp), GFP_KERNEL);
+	if (!pp)
+		return ERR_PTR(-ENOMEM);
+
+	pp->ntb = ntb;
+	atomic_set(&pp->count, 0);
+	spin_lock_init(&pp->lock);
+	hrtimer_init(&pp->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	pp->timer.function = pp_timer_func;
+
+	return pp;
+}
+
+static void pp_init_flds(struct pp_ctx *pp)
+{
+	int pidx, lport, pcnt;
+
+	/* Find global port index */
+	lport = ntb_port_number(pp->ntb);
+	pcnt = ntb_peer_port_count(pp->ntb);
+	for (pidx = 0; pidx < pcnt; pidx++) {
+		if (lport < ntb_peer_port_number(pp->ntb, pidx))
+			break;
+	}
+
+	pp->in_db = BIT_ULL(lport);
+	pp->pmask = GENMASK_ULL(pidx, 0) >> 1;
+	pp->nmask = GENMASK_ULL(pcnt - 1, pidx);
+
+	dev_dbg(&pp->ntb->dev, "Inbound db %#llx, prev %#llx, next %#llx\n",
+		pp->in_db, pp->pmask, pp->nmask);
+}
+
+static int pp_mask_events(struct pp_ctx *pp)
+{
+	u64 db_mask, msg_mask;
+	int ret;
+
+	db_mask = ntb_db_valid_mask(pp->ntb);
+	ret = ntb_db_set_mask(pp->ntb, db_mask);
+	if (ret)
+		return ret;
+
+	/* Skip message events masking if unsupported */
+	if (ntb_msg_count(pp->ntb) < 1)
+		return 0;
+
+	msg_mask = ntb_msg_outbits(pp->ntb) | ntb_msg_inbits(pp->ntb);
+	return ntb_msg_set_mask(pp->ntb, msg_mask);
+}
+
+static int pp_setup_ctx(struct pp_ctx *pp)
+{
+	int ret;
+
+	ret = ntb_set_ctx(pp->ntb, pp, &pp_ops);
+	if (ret)
+		return ret;
+
+	ntb_link_enable(pp->ntb, NTB_SPEED_AUTO, NTB_WIDTH_AUTO);
+	/* Might be not necessary */
+	ntb_link_event(pp->ntb);
+
+	return 0;
+}
+
+static void pp_clear_ctx(struct pp_ctx *pp)
+{
+	ntb_link_disable(pp->ntb);
+
+	ntb_clear_ctx(pp->ntb);
+}
+
+static void pp_setup_dbgfs(struct pp_ctx *pp)
+{
+	struct pci_dev *pdev = pp->ntb->pdev;
+
+	pp->dbgfs_dir = debugfs_create_dir(pci_name(pdev), pp_dbgfs_topdir);
+
+	debugfs_create_atomic_t("count", 0600, pp->dbgfs_dir, &pp->count);
+}
+
+static void pp_clear_dbgfs(struct pp_ctx *pp)
+{
+	debugfs_remove_recursive(pp->dbgfs_dir);
+}
+
+static int pp_probe(struct ntb_client *client, struct ntb_dev *ntb)
+{
+	struct pp_ctx *pp;
+	int ret;
+
+	ret = pp_check_ntb(ntb);
+	if (ret)
+		return ret;
+
+	pp = pp_create_data(ntb);
+	if (IS_ERR(pp))
+		return PTR_ERR(pp);
+
+	pp_init_flds(pp);
+
+	ret = pp_mask_events(pp);
+	if (ret)
+		return ret;
+
+	ret = pp_setup_ctx(pp);
+	if (ret)
+		return ret;
+
+	pp_setup_dbgfs(pp);
+
+	return 0;
+}
+
+static void pp_remove(struct ntb_client *client, struct ntb_dev *ntb)
+{
+	struct pp_ctx *pp = ntb->ctx;
+
+	pp_clear_dbgfs(pp);
+
+	pp_clear_ctx(pp);
+
+	pp_clear(pp);
+}
+
+static struct ntb_client pp_client = {
+	.ops = {
+		.probe = pp_probe,
+		.remove = pp_remove
+	}
+};
+
+static int __init pp_init(void)
+{
+	int ret;
+
+	if (debugfs_initialized())
+		pp_dbgfs_topdir = debugfs_create_dir(KBUILD_MODNAME, NULL);
+
+	ret = ntb_register_client(&pp_client);
+	if (ret)
+		debugfs_remove_recursive(pp_dbgfs_topdir);
+
+	return ret;
+}
+module_init(pp_init);
+
+static void __exit pp_exit(void)
+{
+	ntb_unregister_client(&pp_client);
+	debugfs_remove_recursive(pp_dbgfs_topdir);
+}
+module_exit(pp_exit);
diff --git a/drivers/ntb/test/ntb_tool.c b/drivers/ntb/test/ntb_tool.c
new file mode 100644
index 000000000..eeeb4b1c9
--- /dev/null
+++ b/drivers/ntb/test/ntb_tool.c
@@ -0,0 +1,1696 @@
+/*
+ * This file is provided under a dual BSD/GPLv2 license.  When using or
+ *   redistributing this file, you may do so under either license.
+ *
+ *   GPL LICENSE SUMMARY
+ *
+ *   Copyright (C) 2015 EMC Corporation. All Rights Reserved.
+ *   Copyright (C) 2017 T-Platforms All Rights Reserved.
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of version 2 of the GNU General Public License as
+ *   published by the Free Software Foundation.
+ *
+ *   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
+ *   General Public License for more details.
+ *
+ *   BSD LICENSE
+ *
+ *   Copyright (C) 2015 EMC Corporation. All Rights Reserved.
+ *   Copyright (C) 2017 T-Platforms All Rights Reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copy
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * PCIe NTB Debugging Tool Linux driver
+ */
+
+/*
+ * How to use this tool, by example.
+ *
+ * Assuming $DBG_DIR is something like:
+ * '/sys/kernel/debug/ntb_tool/0000:00:03.0'
+ * Suppose aside from local device there is at least one remote device
+ * connected to NTB with index 0.
+ *-----------------------------------------------------------------------------
+ * Eg: check local/peer device information.
+ *
+ * # Get local device port number
+ * root@self# cat $DBG_DIR/port
+ *
+ * # Check local device functionality
+ * root@self# ls $DBG_DIR
+ * db            msg1          msg_sts     peer4/        port
+ * db_event      msg2          peer0/      peer5/        spad0
+ * db_mask       msg3          peer1/      peer_db       spad1
+ * link          msg_event     peer2/      peer_db_mask  spad2
+ * msg0          msg_mask      peer3/      peer_spad     spad3
+ * # As one can see it supports:
+ * # 1) four inbound message registers
+ * # 2) four inbound scratchpads
+ * # 3) up to six peer devices
+ *
+ * # Check peer device port number
+ * root@self# cat $DBG_DIR/peer0/port
+ *
+ * # Check peer device(s) functionality to be used
+ * root@self# ls $DBG_DIR/peer0
+ * link             mw_trans0       mw_trans6        port
+ * link_event       mw_trans1       mw_trans7        spad0
+ * msg0             mw_trans2       peer_mw_trans0   spad1
+ * msg1             mw_trans3       peer_mw_trans1   spad2
+ * msg2             mw_trans4       peer_mw_trans2   spad3
+ * msg3             mw_trans5       peer_mw_trans3
+ * # As one can see we got:
+ * # 1) four outbound message registers
+ * # 2) four outbound scratchpads
+ * # 3) eight inbound memory windows
+ * # 4) four outbound memory windows
+ *-----------------------------------------------------------------------------
+ * Eg: NTB link tests
+ *
+ * # Set local link up/down
+ * root@self# echo Y > $DBG_DIR/link
+ * root@self# echo N > $DBG_DIR/link
+ *
+ * # Check if link with peer device is up/down:
+ * root@self# cat $DBG_DIR/peer0/link
+ *
+ * # Block until the link is up/down
+ * root@self# echo Y > $DBG_DIR/peer0/link_event
+ * root@self# echo N > $DBG_DIR/peer0/link_event
+ *-----------------------------------------------------------------------------
+ * Eg: Doorbell registers tests (some functionality might be absent)
+ *
+ * # Set/clear/get local doorbell
+ * root@self# echo 's 1' > $DBG_DIR/db
+ * root@self# echo 'c 1' > $DBG_DIR/db
+ * root@self# cat  $DBG_DIR/db
+ *
+ * # Set/clear/get local doorbell mask
+ * root@self# echo 's 1' > $DBG_DIR/db_mask
+ * root@self# echo 'c 1' > $DBG_DIR/db_mask
+ * root@self# cat $DBG_DIR/db_mask
+ *
+ * # Ring/clear/get peer doorbell
+ * root@peer# echo 's 1' > $DBG_DIR/peer_db
+ * root@peer# echo 'c 1' > $DBG_DIR/peer_db
+ * root@peer# cat $DBG_DIR/peer_db
+ *
+ * # Set/clear/get peer doorbell mask
+ * root@self# echo 's 1' > $DBG_DIR/peer_db_mask
+ * root@self# echo 'c 1' > $DBG_DIR/peer_db_mask
+ * root@self# cat $DBG_DIR/peer_db_mask
+ *
+ * # Block until local doorbell is set with specified value
+ * root@self# echo 1 > $DBG_DIR/db_event
+ *-----------------------------------------------------------------------------
+ * Eg: Message registers tests (functionality might be absent)
+ *
+ * # Set/clear/get in/out message registers status
+ * root@self# echo 's 1' > $DBG_DIR/msg_sts
+ * root@self# echo 'c 1' > $DBG_DIR/msg_sts
+ * root@self# cat $DBG_DIR/msg_sts
+ *
+ * # Set/clear in/out message registers mask
+ * root@self# echo 's 1' > $DBG_DIR/msg_mask
+ * root@self# echo 'c 1' > $DBG_DIR/msg_mask
+ *
+ * # Get inbound message register #0 value and source of port index
+ * root@self# cat  $DBG_DIR/msg0
+ *
+ * # Send some data to peer over outbound message register #0
+ * root@self# echo 0x01020304 > $DBG_DIR/peer0/msg0
+ *-----------------------------------------------------------------------------
+ * Eg: Scratchpad registers tests (functionality might be absent)
+ *
+ * # Write/read to/from local scratchpad register #0
+ * root@peer# echo 0x01020304 > $DBG_DIR/spad0
+ * root@peer# cat $DBG_DIR/spad0
+ *
+ * # Write/read to/from peer scratchpad register #0
+ * root@peer# echo 0x01020304 > $DBG_DIR/peer0/spad0
+ * root@peer# cat $DBG_DIR/peer0/spad0
+ *-----------------------------------------------------------------------------
+ * Eg: Memory windows tests
+ *
+ * # Create inbound memory window buffer of specified size/get its base address
+ * root@peer# echo 16384 > $DBG_DIR/peer0/mw_trans0
+ * root@peer# cat $DBG_DIR/peer0/mw_trans0
+ *
+ * # Write/read data to/from inbound memory window
+ * root@peer# echo Hello > $DBG_DIR/peer0/mw0
+ * root@peer# head -c 7 $DBG_DIR/peer0/mw0
+ *
+ * # Map outbound memory window/check it settings (on peer device)
+ * root@peer# echo 0xADD0BA5E:16384 > $DBG_DIR/peer0/peer_mw_trans0
+ * root@peer# cat $DBG_DIR/peer0/peer_mw_trans0
+ *
+ * # Write/read data to/from outbound memory window (on peer device)
+ * root@peer# echo olleH > $DBG_DIR/peer0/peer_mw0
+ * root@peer# head -c 7 $DBG_DIR/peer0/peer_mw0
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+#include <linux/debugfs.h>
+#include <linux/dma-mapping.h>
+#include <linux/pci.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+
+#include <linux/ntb.h>
+
+#define DRIVER_NAME		"ntb_tool"
+#define DRIVER_VERSION		"2.0"
+
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_AUTHOR("Allen Hubbe <Allen.Hubbe@emc.com>");
+MODULE_DESCRIPTION("PCIe NTB Debugging Tool");
+
+/*
+ * Inbound and outbound memory windows descriptor. Union members selection
+ * depends on the MW type the structure describes. mm_base/dma_base are the
+ * virtual and DMA address of an inbound MW. io_base/tr_base are the MMIO
+ * mapped virtual and xlat addresses of an outbound MW respectively.
+ */
+struct tool_mw {
+	int widx;
+	int pidx;
+	struct tool_ctx *tc;
+	union {
+		u8 *mm_base;
+		u8 __iomem *io_base;
+	};
+	union {
+		dma_addr_t dma_base;
+		u64 tr_base;
+	};
+	resource_size_t size;
+	struct dentry *dbgfs_file;
+};
+
+/*
+ * Wrapper structure is used to distinguish the outbound MW peers reference
+ * within the corresponding DebugFS directory IO operation.
+ */
+struct tool_mw_wrap {
+	int pidx;
+	struct tool_mw *mw;
+};
+
+struct tool_msg {
+	int midx;
+	int pidx;
+	struct tool_ctx *tc;
+};
+
+struct tool_spad {
+	int sidx;
+	int pidx;
+	struct tool_ctx *tc;
+};
+
+struct tool_peer {
+	int pidx;
+	struct tool_ctx *tc;
+	int inmw_cnt;
+	struct tool_mw *inmws;
+	int outmw_cnt;
+	struct tool_mw_wrap *outmws;
+	int outmsg_cnt;
+	struct tool_msg *outmsgs;
+	int outspad_cnt;
+	struct tool_spad *outspads;
+	struct dentry *dbgfs_dir;
+};
+
+struct tool_ctx {
+	struct ntb_dev *ntb;
+	wait_queue_head_t link_wq;
+	wait_queue_head_t db_wq;
+	wait_queue_head_t msg_wq;
+	int outmw_cnt;
+	struct tool_mw *outmws;
+	int peer_cnt;
+	struct tool_peer *peers;
+	int inmsg_cnt;
+	struct tool_msg *inmsgs;
+	int inspad_cnt;
+	struct tool_spad *inspads;
+	struct dentry *dbgfs_dir;
+};
+
+#define TOOL_FOPS_RDWR(__name, __read, __write) \
+	const struct file_operations __name = {	\
+		.owner = THIS_MODULE,		\
+		.open = simple_open,		\
+		.read = __read,			\
+		.write = __write,		\
+	}
+
+#define TOOL_BUF_LEN 32
+
+static struct dentry *tool_dbgfs_topdir;
+
+/*==============================================================================
+ *                               NTB events handlers
+ *==============================================================================
+ */
+
+static void tool_link_event(void *ctx)
+{
+	struct tool_ctx *tc = ctx;
+	enum ntb_speed speed;
+	enum ntb_width width;
+	int up;
+
+	up = ntb_link_is_up(tc->ntb, &speed, &width);
+
+	dev_dbg(&tc->ntb->dev, "link is %s speed %d width %d\n",
+		up ? "up" : "down", speed, width);
+
+	wake_up(&tc->link_wq);
+}
+
+static void tool_db_event(void *ctx, int vec)
+{
+	struct tool_ctx *tc = ctx;
+	u64 db_bits, db_mask;
+
+	db_mask = ntb_db_vector_mask(tc->ntb, vec);
+	db_bits = ntb_db_read(tc->ntb);
+
+	dev_dbg(&tc->ntb->dev, "doorbell vec %d mask %#llx bits %#llx\n",
+		vec, db_mask, db_bits);
+
+	wake_up(&tc->db_wq);
+}
+
+static void tool_msg_event(void *ctx)
+{
+	struct tool_ctx *tc = ctx;
+	u64 msg_sts;
+
+	msg_sts = ntb_msg_read_sts(tc->ntb);
+
+	dev_dbg(&tc->ntb->dev, "message bits %#llx\n", msg_sts);
+
+	wake_up(&tc->msg_wq);
+}
+
+static const struct ntb_ctx_ops tool_ops = {
+	.link_event = tool_link_event,
+	.db_event = tool_db_event,
+	.msg_event = tool_msg_event
+};
+
+/*==============================================================================
+ *                        Common read/write methods
+ *==============================================================================
+ */
+
+static ssize_t tool_fn_read(struct tool_ctx *tc, char __user *ubuf,
+			    size_t size, loff_t *offp,
+			    u64 (*fn_read)(struct ntb_dev *))
+{
+	size_t buf_size;
+	char buf[TOOL_BUF_LEN];
+	ssize_t pos;
+
+	if (!fn_read)
+		return -EINVAL;
+
+	buf_size = min(size, sizeof(buf));
+
+	pos = scnprintf(buf, buf_size, "%#llx\n", fn_read(tc->ntb));
+
+	return simple_read_from_buffer(ubuf, size, offp, buf, pos);
+}
+
+static ssize_t tool_fn_write(struct tool_ctx *tc,
+			     const char __user *ubuf,
+			     size_t size, loff_t *offp,
+			     int (*fn_set)(struct ntb_dev *, u64),
+			     int (*fn_clear)(struct ntb_dev *, u64))
+{
+	char *buf, cmd;
+	ssize_t ret;
+	u64 bits;
+	int n;
+
+	if (*offp)
+		return 0;
+
+	buf = kmalloc(size + 1, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	if (copy_from_user(buf, ubuf, size)) {
+		kfree(buf);
+		return -EFAULT;
+	}
+
+	buf[size] = 0;
+
+	n = sscanf(buf, "%c %lli", &cmd, &bits);
+
+	kfree(buf);
+
+	if (n != 2) {
+		ret = -EINVAL;
+	} else if (cmd == 's') {
+		if (!fn_set)
+			ret = -EINVAL;
+		else
+			ret = fn_set(tc->ntb, bits);
+	} else if (cmd == 'c') {
+		if (!fn_clear)
+			ret = -EINVAL;
+		else
+			ret = fn_clear(tc->ntb, bits);
+	} else {
+		ret = -EINVAL;
+	}
+
+	return ret ? : size;
+}
+
+/*==============================================================================
+ *                            Port read/write methods
+ *==============================================================================
+ */
+
+static ssize_t tool_port_read(struct file *filep, char __user *ubuf,
+			      size_t size, loff_t *offp)
+{
+	struct tool_ctx *tc = filep->private_data;
+	char buf[TOOL_BUF_LEN];
+	int pos;
+
+	pos = scnprintf(buf, sizeof(buf), "%d\n", ntb_port_number(tc->ntb));
+
+	return simple_read_from_buffer(ubuf, size, offp, buf, pos);
+}
+
+static TOOL_FOPS_RDWR(tool_port_fops,
+		      tool_port_read,
+		      NULL);
+
+static ssize_t tool_peer_port_read(struct file *filep, char __user *ubuf,
+				   size_t size, loff_t *offp)
+{
+	struct tool_peer *peer = filep->private_data;
+	struct tool_ctx *tc = peer->tc;
+	char buf[TOOL_BUF_LEN];
+	int pos;
+
+	pos = scnprintf(buf, sizeof(buf), "%d\n",
+		ntb_peer_port_number(tc->ntb, peer->pidx));
+
+	return simple_read_from_buffer(ubuf, size, offp, buf, pos);
+}
+
+static TOOL_FOPS_RDWR(tool_peer_port_fops,
+		      tool_peer_port_read,
+		      NULL);
+
+static int tool_init_peers(struct tool_ctx *tc)
+{
+	int pidx;
+
+	tc->peer_cnt = ntb_peer_port_count(tc->ntb);
+	tc->peers = devm_kcalloc(&tc->ntb->dev, tc->peer_cnt,
+				 sizeof(*tc->peers), GFP_KERNEL);
+	if (tc->peers == NULL)
+		return -ENOMEM;
+
+	for (pidx = 0; pidx < tc->peer_cnt; pidx++) {
+		tc->peers[pidx].pidx = pidx;
+		tc->peers[pidx].tc = tc;
+	}
+
+	return 0;
+}
+
+/*==============================================================================
+ *                       Link state read/write methods
+ *==============================================================================
+ */
+
+static ssize_t tool_link_write(struct file *filep, const char __user *ubuf,
+			       size_t size, loff_t *offp)
+{
+	struct tool_ctx *tc = filep->private_data;
+	bool val;
+	int ret;
+
+	ret = kstrtobool_from_user(ubuf, size, &val);
+	if (ret)
+		return ret;
+
+	if (val)
+		ret = ntb_link_enable(tc->ntb, NTB_SPEED_AUTO, NTB_WIDTH_AUTO);
+	else
+		ret = ntb_link_disable(tc->ntb);
+
+	if (ret)
+		return ret;
+
+	return size;
+}
+
+static TOOL_FOPS_RDWR(tool_link_fops,
+		      NULL,
+		      tool_link_write);
+
+static ssize_t tool_peer_link_read(struct file *filep, char __user *ubuf,
+				   size_t size, loff_t *offp)
+{
+	struct tool_peer *peer = filep->private_data;
+	struct tool_ctx *tc = peer->tc;
+	char buf[3];
+
+	if (ntb_link_is_up(tc->ntb, NULL, NULL) & BIT(peer->pidx))
+		buf[0] = 'Y';
+	else
+		buf[0] = 'N';
+	buf[1] = '\n';
+	buf[2] = '\0';
+
+	return simple_read_from_buffer(ubuf, size, offp, buf, 2);
+}
+
+static TOOL_FOPS_RDWR(tool_peer_link_fops,
+		      tool_peer_link_read,
+		      NULL);
+
+static ssize_t tool_peer_link_event_write(struct file *filep,
+					  const char __user *ubuf,
+					  size_t size, loff_t *offp)
+{
+	struct tool_peer *peer = filep->private_data;
+	struct tool_ctx *tc = peer->tc;
+	u64 link_msk;
+	bool val;
+	int ret;
+
+	ret = kstrtobool_from_user(ubuf, size, &val);
+	if (ret)
+		return ret;
+
+	link_msk = BIT_ULL_MASK(peer->pidx);
+
+	if (wait_event_interruptible(tc->link_wq,
+		!!(ntb_link_is_up(tc->ntb, NULL, NULL) & link_msk) == val))
+		return -ERESTART;
+
+	return size;
+}
+
+static TOOL_FOPS_RDWR(tool_peer_link_event_fops,
+		      NULL,
+		      tool_peer_link_event_write);
+
+/*==============================================================================
+ *                  Memory windows read/write/setting methods
+ *==============================================================================
+ */
+
+static ssize_t tool_mw_read(struct file *filep, char __user *ubuf,
+			    size_t size, loff_t *offp)
+{
+	struct tool_mw *inmw = filep->private_data;
+
+	if (inmw->mm_base == NULL)
+		return -ENXIO;
+
+	return simple_read_from_buffer(ubuf, size, offp,
+				       inmw->mm_base, inmw->size);
+}
+
+static ssize_t tool_mw_write(struct file *filep, const char __user *ubuf,
+			     size_t size, loff_t *offp)
+{
+	struct tool_mw *inmw = filep->private_data;
+
+	if (inmw->mm_base == NULL)
+		return -ENXIO;
+
+	return simple_write_to_buffer(inmw->mm_base, inmw->size, offp,
+				      ubuf, size);
+}
+
+static TOOL_FOPS_RDWR(tool_mw_fops,
+		      tool_mw_read,
+		      tool_mw_write);
+
+static int tool_setup_mw(struct tool_ctx *tc, int pidx, int widx,
+			 size_t req_size)
+{
+	resource_size_t size, addr_align, size_align;
+	struct tool_mw *inmw = &tc->peers[pidx].inmws[widx];
+	char buf[TOOL_BUF_LEN];
+	int ret;
+
+	if (inmw->mm_base != NULL)
+		return 0;
+
+	ret = ntb_mw_get_align(tc->ntb, pidx, widx, &addr_align,
+				&size_align, &size);
+	if (ret)
+		return ret;
+
+	inmw->size = min_t(resource_size_t, req_size, size);
+	inmw->size = round_up(inmw->size, addr_align);
+	inmw->size = round_up(inmw->size, size_align);
+	inmw->mm_base = dma_alloc_coherent(&tc->ntb->pdev->dev, inmw->size,
+					   &inmw->dma_base, GFP_KERNEL);
+	if (!inmw->mm_base)
+		return -ENOMEM;
+
+	if (!IS_ALIGNED(inmw->dma_base, addr_align)) {
+		ret = -ENOMEM;
+		goto err_free_dma;
+	}
+
+	ret = ntb_mw_set_trans(tc->ntb, pidx, widx, inmw->dma_base, inmw->size);
+	if (ret)
+		goto err_free_dma;
+
+	snprintf(buf, sizeof(buf), "mw%d", widx);
+	inmw->dbgfs_file = debugfs_create_file(buf, 0600,
+					       tc->peers[pidx].dbgfs_dir, inmw,
+					       &tool_mw_fops);
+
+	return 0;
+
+err_free_dma:
+	dma_free_coherent(&tc->ntb->pdev->dev, inmw->size, inmw->mm_base,
+			  inmw->dma_base);
+	inmw->mm_base = NULL;
+	inmw->dma_base = 0;
+	inmw->size = 0;
+
+	return ret;
+}
+
+static void tool_free_mw(struct tool_ctx *tc, int pidx, int widx)
+{
+	struct tool_mw *inmw = &tc->peers[pidx].inmws[widx];
+
+	debugfs_remove(inmw->dbgfs_file);
+
+	if (inmw->mm_base != NULL) {
+		ntb_mw_clear_trans(tc->ntb, pidx, widx);
+		dma_free_coherent(&tc->ntb->pdev->dev, inmw->size,
+				  inmw->mm_base, inmw->dma_base);
+	}
+
+	inmw->mm_base = NULL;
+	inmw->dma_base = 0;
+	inmw->size = 0;
+	inmw->dbgfs_file = NULL;
+}
+
+static ssize_t tool_mw_trans_read(struct file *filep, char __user *ubuf,
+				  size_t size, loff_t *offp)
+{
+	struct tool_mw *inmw = filep->private_data;
+	resource_size_t addr_align;
+	resource_size_t size_align;
+	resource_size_t size_max;
+	ssize_t ret, off = 0;
+	size_t buf_size;
+	char *buf;
+
+	buf_size = min_t(size_t, size, 512);
+
+	buf = kmalloc(buf_size, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	ret = ntb_mw_get_align(inmw->tc->ntb, inmw->pidx, inmw->widx,
+			       &addr_align, &size_align, &size_max);
+	if (ret)
+		goto err;
+
+	off += scnprintf(buf + off, buf_size - off,
+			 "Inbound MW     \t%d\n",
+			 inmw->widx);
+
+	off += scnprintf(buf + off, buf_size - off,
+			 "Port           \t%d (%d)\n",
+			 ntb_peer_port_number(inmw->tc->ntb, inmw->pidx),
+			 inmw->pidx);
+
+	off += scnprintf(buf + off, buf_size - off,
+			 "Window Address \t0x%pK\n", inmw->mm_base);
+
+	off += scnprintf(buf + off, buf_size - off,
+			 "DMA Address    \t%pad\n",
+			 &inmw->dma_base);
+
+	off += scnprintf(buf + off, buf_size - off,
+			 "Window Size    \t%pap\n",
+			 &inmw->size);
+
+	off += scnprintf(buf + off, buf_size - off,
+			 "Alignment      \t%pap\n",
+			 &addr_align);
+
+	off += scnprintf(buf + off, buf_size - off,
+			 "Size Alignment \t%pap\n",
+			 &size_align);
+
+	off += scnprintf(buf + off, buf_size - off,
+			 "Size Max       \t%pap\n",
+			 &size_max);
+
+	ret = simple_read_from_buffer(ubuf, size, offp, buf, off);
+
+err:
+	kfree(buf);
+
+	return ret;
+}
+
+static ssize_t tool_mw_trans_write(struct file *filep, const char __user *ubuf,
+				   size_t size, loff_t *offp)
+{
+	struct tool_mw *inmw = filep->private_data;
+	unsigned int val;
+	int ret;
+
+	ret = kstrtouint_from_user(ubuf, size, 0, &val);
+	if (ret)
+		return ret;
+
+	tool_free_mw(inmw->tc, inmw->pidx, inmw->widx);
+	if (val) {
+		ret = tool_setup_mw(inmw->tc, inmw->pidx, inmw->widx, val);
+		if (ret)
+			return ret;
+	}
+
+	return size;
+}
+
+static TOOL_FOPS_RDWR(tool_mw_trans_fops,
+		      tool_mw_trans_read,
+		      tool_mw_trans_write);
+
+static ssize_t tool_peer_mw_read(struct file *filep, char __user *ubuf,
+				 size_t size, loff_t *offp)
+{
+	struct tool_mw *outmw = filep->private_data;
+	loff_t pos = *offp;
+	ssize_t ret;
+	void *buf;
+
+	if (outmw->io_base == NULL)
+		return -EIO;
+
+	if (pos >= outmw->size || !size)
+		return 0;
+
+	if (size > outmw->size - pos)
+		size = outmw->size - pos;
+
+	buf = kmalloc(size, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	memcpy_fromio(buf, outmw->io_base + pos, size);
+	ret = copy_to_user(ubuf, buf, size);
+	if (ret == size) {
+		ret = -EFAULT;
+		goto err_free;
+	}
+
+	size -= ret;
+	*offp = pos + size;
+	ret = size;
+
+err_free:
+	kfree(buf);
+
+	return ret;
+}
+
+static ssize_t tool_peer_mw_write(struct file *filep, const char __user *ubuf,
+				  size_t size, loff_t *offp)
+{
+	struct tool_mw *outmw = filep->private_data;
+	ssize_t ret;
+	loff_t pos = *offp;
+	void *buf;
+
+	if (outmw->io_base == NULL)
+		return -EIO;
+
+	if (pos >= outmw->size || !size)
+		return 0;
+	if (size > outmw->size - pos)
+		size = outmw->size - pos;
+
+	buf = kmalloc(size, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	ret = copy_from_user(buf, ubuf, size);
+	if (ret == size) {
+		ret = -EFAULT;
+		goto err_free;
+	}
+
+	size -= ret;
+	*offp = pos + size;
+	ret = size;
+
+	memcpy_toio(outmw->io_base + pos, buf, size);
+
+err_free:
+	kfree(buf);
+
+	return ret;
+}
+
+static TOOL_FOPS_RDWR(tool_peer_mw_fops,
+		      tool_peer_mw_read,
+		      tool_peer_mw_write);
+
+static int tool_setup_peer_mw(struct tool_ctx *tc, int pidx, int widx,
+			      u64 req_addr, size_t req_size)
+{
+	struct tool_mw *outmw = &tc->outmws[widx];
+	resource_size_t map_size;
+	phys_addr_t map_base;
+	char buf[TOOL_BUF_LEN];
+	int ret;
+
+	if (outmw->io_base != NULL)
+		return 0;
+
+	ret = ntb_peer_mw_get_addr(tc->ntb, widx, &map_base, &map_size);
+	if (ret)
+		return ret;
+
+	ret = ntb_peer_mw_set_trans(tc->ntb, pidx, widx, req_addr, req_size);
+	if (ret)
+		return ret;
+
+	outmw->io_base = ioremap_wc(map_base, map_size);
+	if (outmw->io_base == NULL) {
+		ret = -EFAULT;
+		goto err_clear_trans;
+	}
+
+	outmw->tr_base = req_addr;
+	outmw->size = req_size;
+	outmw->pidx = pidx;
+
+	snprintf(buf, sizeof(buf), "peer_mw%d", widx);
+	outmw->dbgfs_file = debugfs_create_file(buf, 0600,
+					       tc->peers[pidx].dbgfs_dir, outmw,
+					       &tool_peer_mw_fops);
+
+	return 0;
+
+err_clear_trans:
+	ntb_peer_mw_clear_trans(tc->ntb, pidx, widx);
+
+	return ret;
+}
+
+static void tool_free_peer_mw(struct tool_ctx *tc, int widx)
+{
+	struct tool_mw *outmw = &tc->outmws[widx];
+
+	debugfs_remove(outmw->dbgfs_file);
+
+	if (outmw->io_base != NULL) {
+		iounmap(tc->outmws[widx].io_base);
+		ntb_peer_mw_clear_trans(tc->ntb, outmw->pidx, widx);
+	}
+
+	outmw->io_base = NULL;
+	outmw->tr_base = 0;
+	outmw->size = 0;
+	outmw->pidx = -1;
+	outmw->dbgfs_file = NULL;
+}
+
+static ssize_t tool_peer_mw_trans_read(struct file *filep, char __user *ubuf,
+					size_t size, loff_t *offp)
+{
+	struct tool_mw_wrap *outmw_wrap = filep->private_data;
+	struct tool_mw *outmw = outmw_wrap->mw;
+	resource_size_t map_size;
+	phys_addr_t map_base;
+	ssize_t off = 0;
+	size_t buf_size;
+	char *buf;
+	int ret;
+
+	ret = ntb_peer_mw_get_addr(outmw->tc->ntb, outmw->widx,
+				  &map_base, &map_size);
+	if (ret)
+		return ret;
+
+	buf_size = min_t(size_t, size, 512);
+
+	buf = kmalloc(buf_size, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	off += scnprintf(buf + off, buf_size - off,
+			 "Outbound MW:        \t%d\n", outmw->widx);
+
+	if (outmw->io_base != NULL) {
+		off += scnprintf(buf + off, buf_size - off,
+			"Port attached       \t%d (%d)\n",
+			ntb_peer_port_number(outmw->tc->ntb, outmw->pidx),
+			outmw->pidx);
+	} else {
+		off += scnprintf(buf + off, buf_size - off,
+				 "Port attached       \t-1 (-1)\n");
+	}
+
+	off += scnprintf(buf + off, buf_size - off,
+			 "Virtual address     \t0x%pK\n", outmw->io_base);
+
+	off += scnprintf(buf + off, buf_size - off,
+			 "Phys Address        \t%pap\n", &map_base);
+
+	off += scnprintf(buf + off, buf_size - off,
+			 "Mapping Size        \t%pap\n", &map_size);
+
+	off += scnprintf(buf + off, buf_size - off,
+			 "Translation Address \t0x%016llx\n", outmw->tr_base);
+
+	off += scnprintf(buf + off, buf_size - off,
+			 "Window Size         \t%pap\n", &outmw->size);
+
+	ret = simple_read_from_buffer(ubuf, size, offp, buf, off);
+	kfree(buf);
+
+	return ret;
+}
+
+static ssize_t tool_peer_mw_trans_write(struct file *filep,
+					const char __user *ubuf,
+					size_t size, loff_t *offp)
+{
+	struct tool_mw_wrap *outmw_wrap = filep->private_data;
+	struct tool_mw *outmw = outmw_wrap->mw;
+	size_t buf_size, wsize;
+	char buf[TOOL_BUF_LEN];
+	int ret, n;
+	u64 addr;
+
+	buf_size = min(size, (sizeof(buf) - 1));
+	if (copy_from_user(buf, ubuf, buf_size))
+		return -EFAULT;
+
+	buf[buf_size] = '\0';
+
+	n = sscanf(buf, "%lli:%zi", &addr, &wsize);
+	if (n != 2)
+		return -EINVAL;
+
+	tool_free_peer_mw(outmw->tc, outmw->widx);
+	if (wsize) {
+		ret = tool_setup_peer_mw(outmw->tc, outmw_wrap->pidx,
+					 outmw->widx, addr, wsize);
+		if (ret)
+			return ret;
+	}
+
+	return size;
+}
+
+static TOOL_FOPS_RDWR(tool_peer_mw_trans_fops,
+		      tool_peer_mw_trans_read,
+		      tool_peer_mw_trans_write);
+
+static int tool_init_mws(struct tool_ctx *tc)
+{
+	int widx, pidx;
+
+	/* Initialize outbound memory windows */
+	tc->outmw_cnt = ntb_peer_mw_count(tc->ntb);
+	tc->outmws = devm_kcalloc(&tc->ntb->dev, tc->outmw_cnt,
+				  sizeof(*tc->outmws), GFP_KERNEL);
+	if (tc->outmws == NULL)
+		return -ENOMEM;
+
+	for (widx = 0; widx < tc->outmw_cnt; widx++) {
+		tc->outmws[widx].widx = widx;
+		tc->outmws[widx].pidx = -1;
+		tc->outmws[widx].tc = tc;
+	}
+
+	/* Initialize inbound memory windows and outbound MWs wrapper */
+	for (pidx = 0; pidx < tc->peer_cnt; pidx++) {
+		tc->peers[pidx].inmw_cnt = ntb_mw_count(tc->ntb, pidx);
+		tc->peers[pidx].inmws =
+			devm_kcalloc(&tc->ntb->dev, tc->peers[pidx].inmw_cnt,
+				    sizeof(*tc->peers[pidx].inmws), GFP_KERNEL);
+		if (tc->peers[pidx].inmws == NULL)
+			return -ENOMEM;
+
+		for (widx = 0; widx < tc->peers[pidx].inmw_cnt; widx++) {
+			tc->peers[pidx].inmws[widx].widx = widx;
+			tc->peers[pidx].inmws[widx].pidx = pidx;
+			tc->peers[pidx].inmws[widx].tc = tc;
+		}
+
+		tc->peers[pidx].outmw_cnt = ntb_peer_mw_count(tc->ntb);
+		tc->peers[pidx].outmws =
+			devm_kcalloc(&tc->ntb->dev, tc->peers[pidx].outmw_cnt,
+				   sizeof(*tc->peers[pidx].outmws), GFP_KERNEL);
+		if (tc->peers[pidx].outmws == NULL)
+			return -ENOMEM;
+
+		for (widx = 0; widx < tc->peers[pidx].outmw_cnt; widx++) {
+			tc->peers[pidx].outmws[widx].pidx = pidx;
+			tc->peers[pidx].outmws[widx].mw = &tc->outmws[widx];
+		}
+	}
+
+	return 0;
+}
+
+static void tool_clear_mws(struct tool_ctx *tc)
+{
+	int widx, pidx;
+
+	/* Free outbound memory windows */
+	for (widx = 0; widx < tc->outmw_cnt; widx++)
+		tool_free_peer_mw(tc, widx);
+
+	/* Free outbound memory windows */
+	for (pidx = 0; pidx < tc->peer_cnt; pidx++)
+		for (widx = 0; widx < tc->peers[pidx].inmw_cnt; widx++)
+			tool_free_mw(tc, pidx, widx);
+}
+
+/*==============================================================================
+ *                       Doorbell read/write methods
+ *==============================================================================
+ */
+
+static ssize_t tool_db_read(struct file *filep, char __user *ubuf,
+			    size_t size, loff_t *offp)
+{
+	struct tool_ctx *tc = filep->private_data;
+
+	return tool_fn_read(tc, ubuf, size, offp, tc->ntb->ops->db_read);
+}
+
+static ssize_t tool_db_write(struct file *filep, const char __user *ubuf,
+			     size_t size, loff_t *offp)
+{
+	struct tool_ctx *tc = filep->private_data;
+
+	return tool_fn_write(tc, ubuf, size, offp, tc->ntb->ops->db_set,
+			     tc->ntb->ops->db_clear);
+}
+
+static TOOL_FOPS_RDWR(tool_db_fops,
+		      tool_db_read,
+		      tool_db_write);
+
+static ssize_t tool_db_valid_mask_read(struct file *filep, char __user *ubuf,
+				       size_t size, loff_t *offp)
+{
+	struct tool_ctx *tc = filep->private_data;
+
+	return tool_fn_read(tc, ubuf, size, offp, tc->ntb->ops->db_valid_mask);
+}
+
+static TOOL_FOPS_RDWR(tool_db_valid_mask_fops,
+		      tool_db_valid_mask_read,
+		      NULL);
+
+static ssize_t tool_db_mask_read(struct file *filep, char __user *ubuf,
+				 size_t size, loff_t *offp)
+{
+	struct tool_ctx *tc = filep->private_data;
+
+	return tool_fn_read(tc, ubuf, size, offp, tc->ntb->ops->db_read_mask);
+}
+
+static ssize_t tool_db_mask_write(struct file *filep, const char __user *ubuf,
+			       size_t size, loff_t *offp)
+{
+	struct tool_ctx *tc = filep->private_data;
+
+	return tool_fn_write(tc, ubuf, size, offp, tc->ntb->ops->db_set_mask,
+			     tc->ntb->ops->db_clear_mask);
+}
+
+static TOOL_FOPS_RDWR(tool_db_mask_fops,
+		      tool_db_mask_read,
+		      tool_db_mask_write);
+
+static ssize_t tool_peer_db_read(struct file *filep, char __user *ubuf,
+				 size_t size, loff_t *offp)
+{
+	struct tool_ctx *tc = filep->private_data;
+
+	return tool_fn_read(tc, ubuf, size, offp, tc->ntb->ops->peer_db_read);
+}
+
+static ssize_t tool_peer_db_write(struct file *filep, const char __user *ubuf,
+				  size_t size, loff_t *offp)
+{
+	struct tool_ctx *tc = filep->private_data;
+
+	return tool_fn_write(tc, ubuf, size, offp, tc->ntb->ops->peer_db_set,
+			     tc->ntb->ops->peer_db_clear);
+}
+
+static TOOL_FOPS_RDWR(tool_peer_db_fops,
+		      tool_peer_db_read,
+		      tool_peer_db_write);
+
+static ssize_t tool_peer_db_mask_read(struct file *filep, char __user *ubuf,
+				   size_t size, loff_t *offp)
+{
+	struct tool_ctx *tc = filep->private_data;
+
+	return tool_fn_read(tc, ubuf, size, offp,
+			    tc->ntb->ops->peer_db_read_mask);
+}
+
+static ssize_t tool_peer_db_mask_write(struct file *filep,
+				       const char __user *ubuf,
+				       size_t size, loff_t *offp)
+{
+	struct tool_ctx *tc = filep->private_data;
+
+	return tool_fn_write(tc, ubuf, size, offp,
+			     tc->ntb->ops->peer_db_set_mask,
+			     tc->ntb->ops->peer_db_clear_mask);
+}
+
+static TOOL_FOPS_RDWR(tool_peer_db_mask_fops,
+		      tool_peer_db_mask_read,
+		      tool_peer_db_mask_write);
+
+static ssize_t tool_db_event_write(struct file *filep,
+				   const char __user *ubuf,
+				   size_t size, loff_t *offp)
+{
+	struct tool_ctx *tc = filep->private_data;
+	u64 val;
+	int ret;
+
+	ret = kstrtou64_from_user(ubuf, size, 0, &val);
+	if (ret)
+		return ret;
+
+	if (wait_event_interruptible(tc->db_wq, ntb_db_read(tc->ntb) == val))
+		return -ERESTART;
+
+	return size;
+}
+
+static TOOL_FOPS_RDWR(tool_db_event_fops,
+		      NULL,
+		      tool_db_event_write);
+
+/*==============================================================================
+ *                       Scratchpads read/write methods
+ *==============================================================================
+ */
+
+static ssize_t tool_spad_read(struct file *filep, char __user *ubuf,
+			      size_t size, loff_t *offp)
+{
+	struct tool_spad *spad = filep->private_data;
+	char buf[TOOL_BUF_LEN];
+	ssize_t pos;
+
+	if (!spad->tc->ntb->ops->spad_read)
+		return -EINVAL;
+
+	pos = scnprintf(buf, sizeof(buf), "%#x\n",
+		ntb_spad_read(spad->tc->ntb, spad->sidx));
+
+	return simple_read_from_buffer(ubuf, size, offp, buf, pos);
+}
+
+static ssize_t tool_spad_write(struct file *filep, const char __user *ubuf,
+			       size_t size, loff_t *offp)
+{
+	struct tool_spad *spad = filep->private_data;
+	u32 val;
+	int ret;
+
+	if (!spad->tc->ntb->ops->spad_write) {
+		dev_dbg(&spad->tc->ntb->dev, "no spad write fn\n");
+		return -EINVAL;
+	}
+
+	ret = kstrtou32_from_user(ubuf, size, 0, &val);
+	if (ret)
+		return ret;
+
+	ret = ntb_spad_write(spad->tc->ntb, spad->sidx, val);
+
+	return ret ?: size;
+}
+
+static TOOL_FOPS_RDWR(tool_spad_fops,
+		      tool_spad_read,
+		      tool_spad_write);
+
+static ssize_t tool_peer_spad_read(struct file *filep, char __user *ubuf,
+				   size_t size, loff_t *offp)
+{
+	struct tool_spad *spad = filep->private_data;
+	char buf[TOOL_BUF_LEN];
+	ssize_t pos;
+
+	if (!spad->tc->ntb->ops->peer_spad_read)
+		return -EINVAL;
+
+	pos = scnprintf(buf, sizeof(buf), "%#x\n",
+		ntb_peer_spad_read(spad->tc->ntb, spad->pidx, spad->sidx));
+
+	return simple_read_from_buffer(ubuf, size, offp, buf, pos);
+}
+
+static ssize_t tool_peer_spad_write(struct file *filep, const char __user *ubuf,
+				    size_t size, loff_t *offp)
+{
+	struct tool_spad *spad = filep->private_data;
+	u32 val;
+	int ret;
+
+	if (!spad->tc->ntb->ops->peer_spad_write) {
+		dev_dbg(&spad->tc->ntb->dev, "no spad write fn\n");
+		return -EINVAL;
+	}
+
+	ret = kstrtou32_from_user(ubuf, size, 0, &val);
+	if (ret)
+		return ret;
+
+	ret = ntb_peer_spad_write(spad->tc->ntb, spad->pidx, spad->sidx, val);
+
+	return ret ?: size;
+}
+
+static TOOL_FOPS_RDWR(tool_peer_spad_fops,
+		      tool_peer_spad_read,
+		      tool_peer_spad_write);
+
+static int tool_init_spads(struct tool_ctx *tc)
+{
+	int sidx, pidx;
+
+	/* Initialize inbound scratchpad structures */
+	tc->inspad_cnt = ntb_spad_count(tc->ntb);
+	tc->inspads = devm_kcalloc(&tc->ntb->dev, tc->inspad_cnt,
+				   sizeof(*tc->inspads), GFP_KERNEL);
+	if (tc->inspads == NULL)
+		return -ENOMEM;
+
+	for (sidx = 0; sidx < tc->inspad_cnt; sidx++) {
+		tc->inspads[sidx].sidx = sidx;
+		tc->inspads[sidx].pidx = -1;
+		tc->inspads[sidx].tc = tc;
+	}
+
+	/* Initialize outbound scratchpad structures */
+	for (pidx = 0; pidx < tc->peer_cnt; pidx++) {
+		tc->peers[pidx].outspad_cnt = ntb_spad_count(tc->ntb);
+		tc->peers[pidx].outspads =
+			devm_kcalloc(&tc->ntb->dev, tc->peers[pidx].outspad_cnt,
+				sizeof(*tc->peers[pidx].outspads), GFP_KERNEL);
+		if (tc->peers[pidx].outspads == NULL)
+			return -ENOMEM;
+
+		for (sidx = 0; sidx < tc->peers[pidx].outspad_cnt; sidx++) {
+			tc->peers[pidx].outspads[sidx].sidx = sidx;
+			tc->peers[pidx].outspads[sidx].pidx = pidx;
+			tc->peers[pidx].outspads[sidx].tc = tc;
+		}
+	}
+
+	return 0;
+}
+
+/*==============================================================================
+ *                       Messages read/write methods
+ *==============================================================================
+ */
+
+static ssize_t tool_inmsg_read(struct file *filep, char __user *ubuf,
+			       size_t size, loff_t *offp)
+{
+	struct tool_msg *msg = filep->private_data;
+	char buf[TOOL_BUF_LEN];
+	ssize_t pos;
+	u32 data;
+	int pidx;
+
+	data = ntb_msg_read(msg->tc->ntb, &pidx, msg->midx);
+
+	pos = scnprintf(buf, sizeof(buf), "0x%08x<-%d\n", data, pidx);
+
+	return simple_read_from_buffer(ubuf, size, offp, buf, pos);
+}
+
+static TOOL_FOPS_RDWR(tool_inmsg_fops,
+		      tool_inmsg_read,
+		      NULL);
+
+static ssize_t tool_outmsg_write(struct file *filep,
+				 const char __user *ubuf,
+				 size_t size, loff_t *offp)
+{
+	struct tool_msg *msg = filep->private_data;
+	u32 val;
+	int ret;
+
+	ret = kstrtou32_from_user(ubuf, size, 0, &val);
+	if (ret)
+		return ret;
+
+	ret = ntb_peer_msg_write(msg->tc->ntb, msg->pidx, msg->midx, val);
+
+	return ret ? : size;
+}
+
+static TOOL_FOPS_RDWR(tool_outmsg_fops,
+		      NULL,
+		      tool_outmsg_write);
+
+static ssize_t tool_msg_sts_read(struct file *filep, char __user *ubuf,
+				 size_t size, loff_t *offp)
+{
+	struct tool_ctx *tc = filep->private_data;
+
+	return tool_fn_read(tc, ubuf, size, offp, tc->ntb->ops->msg_read_sts);
+}
+
+static ssize_t tool_msg_sts_write(struct file *filep, const char __user *ubuf,
+				  size_t size, loff_t *offp)
+{
+	struct tool_ctx *tc = filep->private_data;
+
+	return tool_fn_write(tc, ubuf, size, offp, NULL,
+			     tc->ntb->ops->msg_clear_sts);
+}
+
+static TOOL_FOPS_RDWR(tool_msg_sts_fops,
+		      tool_msg_sts_read,
+		      tool_msg_sts_write);
+
+static ssize_t tool_msg_inbits_read(struct file *filep, char __user *ubuf,
+				    size_t size, loff_t *offp)
+{
+	struct tool_ctx *tc = filep->private_data;
+
+	return tool_fn_read(tc, ubuf, size, offp, tc->ntb->ops->msg_inbits);
+}
+
+static TOOL_FOPS_RDWR(tool_msg_inbits_fops,
+		      tool_msg_inbits_read,
+		      NULL);
+
+static ssize_t tool_msg_outbits_read(struct file *filep, char __user *ubuf,
+				     size_t size, loff_t *offp)
+{
+	struct tool_ctx *tc = filep->private_data;
+
+	return tool_fn_read(tc, ubuf, size, offp, tc->ntb->ops->msg_outbits);
+}
+
+static TOOL_FOPS_RDWR(tool_msg_outbits_fops,
+		      tool_msg_outbits_read,
+		      NULL);
+
+static ssize_t tool_msg_mask_write(struct file *filep, const char __user *ubuf,
+				   size_t size, loff_t *offp)
+{
+	struct tool_ctx *tc = filep->private_data;
+
+	return tool_fn_write(tc, ubuf, size, offp,
+			     tc->ntb->ops->msg_set_mask,
+			     tc->ntb->ops->msg_clear_mask);
+}
+
+static TOOL_FOPS_RDWR(tool_msg_mask_fops,
+		      NULL,
+		      tool_msg_mask_write);
+
+static ssize_t tool_msg_event_write(struct file *filep,
+				    const char __user *ubuf,
+				    size_t size, loff_t *offp)
+{
+	struct tool_ctx *tc = filep->private_data;
+	u64 val;
+	int ret;
+
+	ret = kstrtou64_from_user(ubuf, size, 0, &val);
+	if (ret)
+		return ret;
+
+	if (wait_event_interruptible(tc->msg_wq,
+		ntb_msg_read_sts(tc->ntb) == val))
+		return -ERESTART;
+
+	return size;
+}
+
+static TOOL_FOPS_RDWR(tool_msg_event_fops,
+		      NULL,
+		      tool_msg_event_write);
+
+static int tool_init_msgs(struct tool_ctx *tc)
+{
+	int midx, pidx;
+
+	/* Initialize inbound message structures */
+	tc->inmsg_cnt = ntb_msg_count(tc->ntb);
+	tc->inmsgs = devm_kcalloc(&tc->ntb->dev, tc->inmsg_cnt,
+				   sizeof(*tc->inmsgs), GFP_KERNEL);
+	if (tc->inmsgs == NULL)
+		return -ENOMEM;
+
+	for (midx = 0; midx < tc->inmsg_cnt; midx++) {
+		tc->inmsgs[midx].midx = midx;
+		tc->inmsgs[midx].pidx = -1;
+		tc->inmsgs[midx].tc = tc;
+	}
+
+	/* Initialize outbound message structures */
+	for (pidx = 0; pidx < tc->peer_cnt; pidx++) {
+		tc->peers[pidx].outmsg_cnt = ntb_msg_count(tc->ntb);
+		tc->peers[pidx].outmsgs =
+			devm_kcalloc(&tc->ntb->dev, tc->peers[pidx].outmsg_cnt,
+				sizeof(*tc->peers[pidx].outmsgs), GFP_KERNEL);
+		if (tc->peers[pidx].outmsgs == NULL)
+			return -ENOMEM;
+
+		for (midx = 0; midx < tc->peers[pidx].outmsg_cnt; midx++) {
+			tc->peers[pidx].outmsgs[midx].midx = midx;
+			tc->peers[pidx].outmsgs[midx].pidx = pidx;
+			tc->peers[pidx].outmsgs[midx].tc = tc;
+		}
+	}
+
+	return 0;
+}
+
+/*==============================================================================
+ *                          Initialization methods
+ *==============================================================================
+ */
+
+static struct tool_ctx *tool_create_data(struct ntb_dev *ntb)
+{
+	struct tool_ctx *tc;
+
+	tc = devm_kzalloc(&ntb->dev, sizeof(*tc), GFP_KERNEL);
+	if (tc == NULL)
+		return ERR_PTR(-ENOMEM);
+
+	tc->ntb = ntb;
+	init_waitqueue_head(&tc->link_wq);
+	init_waitqueue_head(&tc->db_wq);
+	init_waitqueue_head(&tc->msg_wq);
+
+	if (ntb_db_is_unsafe(ntb))
+		dev_dbg(&ntb->dev, "doorbell is unsafe\n");
+
+	if (ntb_spad_is_unsafe(ntb))
+		dev_dbg(&ntb->dev, "scratchpad is unsafe\n");
+
+	return tc;
+}
+
+static void tool_clear_data(struct tool_ctx *tc)
+{
+	wake_up(&tc->link_wq);
+	wake_up(&tc->db_wq);
+	wake_up(&tc->msg_wq);
+}
+
+static int tool_init_ntb(struct tool_ctx *tc)
+{
+	return ntb_set_ctx(tc->ntb, tc, &tool_ops);
+}
+
+static void tool_clear_ntb(struct tool_ctx *tc)
+{
+	ntb_clear_ctx(tc->ntb);
+	ntb_link_disable(tc->ntb);
+}
+
+static void tool_setup_dbgfs(struct tool_ctx *tc)
+{
+	int pidx, widx, sidx, midx;
+	char buf[TOOL_BUF_LEN];
+
+	/* This modules is useless without dbgfs... */
+	if (!tool_dbgfs_topdir) {
+		tc->dbgfs_dir = NULL;
+		return;
+	}
+
+	tc->dbgfs_dir = debugfs_create_dir(dev_name(&tc->ntb->dev),
+					   tool_dbgfs_topdir);
+	if (!tc->dbgfs_dir)
+		return;
+
+	debugfs_create_file("port", 0600, tc->dbgfs_dir,
+			    tc, &tool_port_fops);
+
+	debugfs_create_file("link", 0600, tc->dbgfs_dir,
+			    tc, &tool_link_fops);
+
+	debugfs_create_file("db", 0600, tc->dbgfs_dir,
+			    tc, &tool_db_fops);
+
+	debugfs_create_file("db_valid_mask", 0600, tc->dbgfs_dir,
+			    tc, &tool_db_valid_mask_fops);
+
+	debugfs_create_file("db_mask", 0600, tc->dbgfs_dir,
+			    tc, &tool_db_mask_fops);
+
+	debugfs_create_file("db_event", 0600, tc->dbgfs_dir,
+			    tc, &tool_db_event_fops);
+
+	debugfs_create_file("peer_db", 0600, tc->dbgfs_dir,
+			    tc, &tool_peer_db_fops);
+
+	debugfs_create_file("peer_db_mask", 0600, tc->dbgfs_dir,
+			    tc, &tool_peer_db_mask_fops);
+
+	if (tc->inspad_cnt != 0) {
+		for (sidx = 0; sidx < tc->inspad_cnt; sidx++) {
+			snprintf(buf, sizeof(buf), "spad%d", sidx);
+
+			debugfs_create_file(buf, 0600, tc->dbgfs_dir,
+					   &tc->inspads[sidx], &tool_spad_fops);
+		}
+	}
+
+	if (tc->inmsg_cnt != 0) {
+		for (midx = 0; midx < tc->inmsg_cnt; midx++) {
+			snprintf(buf, sizeof(buf), "msg%d", midx);
+			debugfs_create_file(buf, 0600, tc->dbgfs_dir,
+					   &tc->inmsgs[midx], &tool_inmsg_fops);
+		}
+
+		debugfs_create_file("msg_sts", 0600, tc->dbgfs_dir,
+				    tc, &tool_msg_sts_fops);
+
+		debugfs_create_file("msg_inbits", 0600, tc->dbgfs_dir,
+				    tc, &tool_msg_inbits_fops);
+
+		debugfs_create_file("msg_outbits", 0600, tc->dbgfs_dir,
+				    tc, &tool_msg_outbits_fops);
+
+		debugfs_create_file("msg_mask", 0600, tc->dbgfs_dir,
+				    tc, &tool_msg_mask_fops);
+
+		debugfs_create_file("msg_event", 0600, tc->dbgfs_dir,
+				    tc, &tool_msg_event_fops);
+	}
+
+	for (pidx = 0; pidx < tc->peer_cnt; pidx++) {
+		snprintf(buf, sizeof(buf), "peer%d", pidx);
+		tc->peers[pidx].dbgfs_dir =
+			debugfs_create_dir(buf, tc->dbgfs_dir);
+
+		debugfs_create_file("port", 0600,
+				    tc->peers[pidx].dbgfs_dir,
+				    &tc->peers[pidx], &tool_peer_port_fops);
+
+		debugfs_create_file("link", 0200,
+				    tc->peers[pidx].dbgfs_dir,
+				    &tc->peers[pidx], &tool_peer_link_fops);
+
+		debugfs_create_file("link_event", 0200,
+				  tc->peers[pidx].dbgfs_dir,
+				  &tc->peers[pidx], &tool_peer_link_event_fops);
+
+		for (widx = 0; widx < tc->peers[pidx].inmw_cnt; widx++) {
+			snprintf(buf, sizeof(buf), "mw_trans%d", widx);
+			debugfs_create_file(buf, 0600,
+					    tc->peers[pidx].dbgfs_dir,
+					    &tc->peers[pidx].inmws[widx],
+					    &tool_mw_trans_fops);
+		}
+
+		for (widx = 0; widx < tc->peers[pidx].outmw_cnt; widx++) {
+			snprintf(buf, sizeof(buf), "peer_mw_trans%d", widx);
+			debugfs_create_file(buf, 0600,
+					    tc->peers[pidx].dbgfs_dir,
+					    &tc->peers[pidx].outmws[widx],
+					    &tool_peer_mw_trans_fops);
+		}
+
+		for (sidx = 0; sidx < tc->peers[pidx].outspad_cnt; sidx++) {
+			snprintf(buf, sizeof(buf), "spad%d", sidx);
+
+			debugfs_create_file(buf, 0600,
+					    tc->peers[pidx].dbgfs_dir,
+					    &tc->peers[pidx].outspads[sidx],
+					    &tool_peer_spad_fops);
+		}
+
+		for (midx = 0; midx < tc->peers[pidx].outmsg_cnt; midx++) {
+			snprintf(buf, sizeof(buf), "msg%d", midx);
+			debugfs_create_file(buf, 0600,
+					    tc->peers[pidx].dbgfs_dir,
+					    &tc->peers[pidx].outmsgs[midx],
+					    &tool_outmsg_fops);
+		}
+	}
+}
+
+static void tool_clear_dbgfs(struct tool_ctx *tc)
+{
+	debugfs_remove_recursive(tc->dbgfs_dir);
+}
+
+static int tool_probe(struct ntb_client *self, struct ntb_dev *ntb)
+{
+	struct tool_ctx *tc;
+	int ret;
+
+	tc = tool_create_data(ntb);
+	if (IS_ERR(tc))
+		return PTR_ERR(tc);
+
+	ret = tool_init_peers(tc);
+	if (ret != 0)
+		goto err_clear_data;
+
+	ret = tool_init_mws(tc);
+	if (ret != 0)
+		goto err_clear_data;
+
+	ret = tool_init_spads(tc);
+	if (ret != 0)
+		goto err_clear_mws;
+
+	ret = tool_init_msgs(tc);
+	if (ret != 0)
+		goto err_clear_mws;
+
+	ret = tool_init_ntb(tc);
+	if (ret != 0)
+		goto err_clear_mws;
+
+	tool_setup_dbgfs(tc);
+
+	return 0;
+
+err_clear_mws:
+	tool_clear_mws(tc);
+
+err_clear_data:
+	tool_clear_data(tc);
+
+	return ret;
+}
+
+static void tool_remove(struct ntb_client *self, struct ntb_dev *ntb)
+{
+	struct tool_ctx *tc = ntb->ctx;
+
+	tool_clear_dbgfs(tc);
+
+	tool_clear_ntb(tc);
+
+	tool_clear_mws(tc);
+
+	tool_clear_data(tc);
+}
+
+static struct ntb_client tool_client = {
+	.ops = {
+		.probe = tool_probe,
+		.remove = tool_remove,
+	}
+};
+
+static int __init tool_init(void)
+{
+	int ret;
+
+	if (debugfs_initialized())
+		tool_dbgfs_topdir = debugfs_create_dir(KBUILD_MODNAME, NULL);
+
+	ret = ntb_register_client(&tool_client);
+	if (ret)
+		debugfs_remove_recursive(tool_dbgfs_topdir);
+
+	return ret;
+}
+module_init(tool_init);
+
+static void __exit tool_exit(void)
+{
+	ntb_unregister_client(&tool_client);
+	debugfs_remove_recursive(tool_dbgfs_topdir);
+}
+module_exit(tool_exit);