linux/drivers/ntb/ntb.c
Allen Hubbe a1bd3baeb2 NTB: Add NTB hardware abstraction layer
Abstract the NTB device behind a programming interface, so that it can
support different hardware and client drivers.

Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-07-04 14:04:44 -04:00

252 lines
6.3 KiB
C

/*
* 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.
*
* 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.
*
* 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 Linux driver
*
* Contact Information:
* Allen Hubbe <Allen.Hubbe@emc.com>
*/
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/ntb.h>
#include <linux/pci.h>
#define DRIVER_NAME "ntb"
#define DRIVER_DESCRIPTION "PCIe NTB Driver Framework"
#define DRIVER_LICENSE "Dual BSD/GPL"
#define DRIVER_VERSION "1.0"
#define DRIVER_RELDATE "24 March 2015"
#define DRIVER_AUTHOR "Allen Hubbe <Allen.Hubbe@emc.com>"
MODULE_LICENSE(DRIVER_LICENSE);
MODULE_VERSION(DRIVER_VERSION);
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESCRIPTION);
static struct bus_type ntb_bus;
static void ntb_dev_release(struct device *dev);
int __ntb_register_client(struct ntb_client *client, struct module *mod,
const char *mod_name)
{
if (!client)
return -EINVAL;
if (!ntb_client_ops_is_valid(&client->ops))
return -EINVAL;
memset(&client->drv, 0, sizeof(client->drv));
client->drv.bus = &ntb_bus;
client->drv.name = mod_name;
client->drv.owner = mod;
return driver_register(&client->drv);
}
EXPORT_SYMBOL(__ntb_register_client);
void ntb_unregister_client(struct ntb_client *client)
{
driver_unregister(&client->drv);
}
EXPORT_SYMBOL(ntb_unregister_client);
int ntb_register_device(struct ntb_dev *ntb)
{
if (!ntb)
return -EINVAL;
if (!ntb->pdev)
return -EINVAL;
if (!ntb->ops)
return -EINVAL;
if (!ntb_dev_ops_is_valid(ntb->ops))
return -EINVAL;
init_completion(&ntb->released);
memset(&ntb->dev, 0, sizeof(ntb->dev));
ntb->dev.bus = &ntb_bus;
ntb->dev.parent = &ntb->pdev->dev;
ntb->dev.release = ntb_dev_release;
dev_set_name(&ntb->dev, pci_name(ntb->pdev));
ntb->ctx = NULL;
ntb->ctx_ops = NULL;
spin_lock_init(&ntb->ctx_lock);
return device_register(&ntb->dev);
}
EXPORT_SYMBOL(ntb_register_device);
void ntb_unregister_device(struct ntb_dev *ntb)
{
device_unregister(&ntb->dev);
wait_for_completion(&ntb->released);
}
EXPORT_SYMBOL(ntb_unregister_device);
int ntb_set_ctx(struct ntb_dev *ntb, void *ctx,
const struct ntb_ctx_ops *ctx_ops)
{
unsigned long irqflags;
if (!ntb_ctx_ops_is_valid(ctx_ops))
return -EINVAL;
if (ntb->ctx_ops)
return -EINVAL;
spin_lock_irqsave(&ntb->ctx_lock, irqflags);
{
ntb->ctx = ctx;
ntb->ctx_ops = ctx_ops;
}
spin_unlock_irqrestore(&ntb->ctx_lock, irqflags);
return 0;
}
EXPORT_SYMBOL(ntb_set_ctx);
void ntb_clear_ctx(struct ntb_dev *ntb)
{
unsigned long irqflags;
spin_lock_irqsave(&ntb->ctx_lock, irqflags);
{
ntb->ctx_ops = NULL;
ntb->ctx = NULL;
}
spin_unlock_irqrestore(&ntb->ctx_lock, irqflags);
}
EXPORT_SYMBOL(ntb_clear_ctx);
void ntb_link_event(struct ntb_dev *ntb)
{
unsigned long irqflags;
spin_lock_irqsave(&ntb->ctx_lock, irqflags);
{
if (ntb->ctx_ops && ntb->ctx_ops->link_event)
ntb->ctx_ops->link_event(ntb->ctx);
}
spin_unlock_irqrestore(&ntb->ctx_lock, irqflags);
}
EXPORT_SYMBOL(ntb_link_event);
void ntb_db_event(struct ntb_dev *ntb, int vector)
{
unsigned long irqflags;
spin_lock_irqsave(&ntb->ctx_lock, irqflags);
{
if (ntb->ctx_ops && ntb->ctx_ops->db_event)
ntb->ctx_ops->db_event(ntb->ctx, vector);
}
spin_unlock_irqrestore(&ntb->ctx_lock, irqflags);
}
EXPORT_SYMBOL(ntb_db_event);
static int ntb_probe(struct device *dev)
{
struct ntb_dev *ntb;
struct ntb_client *client;
int rc;
get_device(dev);
ntb = dev_ntb(dev);
client = drv_ntb_client(dev->driver);
rc = client->ops.probe(client, ntb);
if (rc)
put_device(dev);
return rc;
}
static int ntb_remove(struct device *dev)
{
struct ntb_dev *ntb;
struct ntb_client *client;
if (dev->driver) {
ntb = dev_ntb(dev);
client = drv_ntb_client(dev->driver);
client->ops.remove(client, ntb);
put_device(dev);
}
return 0;
}
static void ntb_dev_release(struct device *dev)
{
struct ntb_dev *ntb = dev_ntb(dev);
complete(&ntb->released);
}
static struct bus_type ntb_bus = {
.name = "ntb",
.probe = ntb_probe,
.remove = ntb_remove,
};
static int __init ntb_driver_init(void)
{
return bus_register(&ntb_bus);
}
module_init(ntb_driver_init);
static void __exit ntb_driver_exit(void)
{
bus_unregister(&ntb_bus);
}
module_exit(ntb_driver_exit);