1 /*
2  * This file is provided under a dual BSD/GPLv2 license.  When using or
3  *   redistributing this file, you may do so under either license.
4  *
5  *   GPL LICENSE SUMMARY
6  *
7  *   Copyright (C) 2015 EMC Corporation. All Rights Reserved.
8  *
9  *   This program is free software; you can redistribute it and/or modify
10  *   it under the terms of version 2 of the GNU General Public License as
11  *   published by the Free Software Foundation.
12  *
13  *   This program is distributed in the hope that it will be useful, but
14  *   WITHOUT ANY WARRANTY; without even the implied warranty of
15  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  *   General Public License for more details.
17  *
18  *   BSD LICENSE
19  *
20  *   Copyright (C) 2015 EMC Corporation. All Rights Reserved.
21  *
22  *   Redistribution and use in source and binary forms, with or without
23  *   modification, are permitted provided that the following conditions
24  *   are met:
25  *
26  *     * Redistributions of source code must retain the above copyright
27  *       notice, this list of conditions and the following disclaimer.
28  *     * Redistributions in binary form must reproduce the above copy
29  *       notice, this list of conditions and the following disclaimer in
30  *       the documentation and/or other materials provided with the
31  *       distribution.
32  *     * Neither the name of Intel Corporation nor the names of its
33  *       contributors may be used to endorse or promote products derived
34  *       from this software without specific prior written permission.
35  *
36  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
37  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
38  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
39  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
40  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
41  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
42  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
43  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
44  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
45  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
46  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
47  *
48  * PCIe NTB Linux driver
49  *
50  * Contact Information:
51  * Allen Hubbe <Allen.Hubbe@emc.com>
52  */
53 
54 #include <linux/device.h>
55 #include <linux/kernel.h>
56 #include <linux/module.h>
57 
58 #include <linux/ntb.h>
59 #include <linux/pci.h>
60 
61 #define DRIVER_NAME			"ntb"
62 #define DRIVER_DESCRIPTION		"PCIe NTB Driver Framework"
63 
64 #define DRIVER_LICENSE			"Dual BSD/GPL"
65 #define DRIVER_VERSION			"1.0"
66 #define DRIVER_RELDATE			"24 March 2015"
67 #define DRIVER_AUTHOR			"Allen Hubbe <Allen.Hubbe@emc.com>"
68 
69 MODULE_LICENSE(DRIVER_LICENSE);
70 MODULE_VERSION(DRIVER_VERSION);
71 MODULE_AUTHOR(DRIVER_AUTHOR);
72 MODULE_DESCRIPTION(DRIVER_DESCRIPTION);
73 
74 static struct bus_type ntb_bus;
75 static void ntb_dev_release(struct device *dev);
76 
__ntb_register_client(struct ntb_client * client,struct module * mod,const char * mod_name)77 int __ntb_register_client(struct ntb_client *client, struct module *mod,
78 			  const char *mod_name)
79 {
80 	if (!client)
81 		return -EINVAL;
82 	if (!ntb_client_ops_is_valid(&client->ops))
83 		return -EINVAL;
84 
85 	memset(&client->drv, 0, sizeof(client->drv));
86 	client->drv.bus = &ntb_bus;
87 	client->drv.name = mod_name;
88 	client->drv.owner = mod;
89 
90 	return driver_register(&client->drv);
91 }
92 EXPORT_SYMBOL(__ntb_register_client);
93 
ntb_unregister_client(struct ntb_client * client)94 void ntb_unregister_client(struct ntb_client *client)
95 {
96 	driver_unregister(&client->drv);
97 }
98 EXPORT_SYMBOL(ntb_unregister_client);
99 
ntb_register_device(struct ntb_dev * ntb)100 int ntb_register_device(struct ntb_dev *ntb)
101 {
102 	if (!ntb)
103 		return -EINVAL;
104 	if (!ntb->pdev)
105 		return -EINVAL;
106 	if (!ntb->ops)
107 		return -EINVAL;
108 	if (!ntb_dev_ops_is_valid(ntb->ops))
109 		return -EINVAL;
110 
111 	init_completion(&ntb->released);
112 
113 	memset(&ntb->dev, 0, sizeof(ntb->dev));
114 	ntb->dev.bus = &ntb_bus;
115 	ntb->dev.parent = &ntb->pdev->dev;
116 	ntb->dev.release = ntb_dev_release;
117 	dev_set_name(&ntb->dev, "%s", pci_name(ntb->pdev));
118 
119 	ntb->ctx = NULL;
120 	ntb->ctx_ops = NULL;
121 	spin_lock_init(&ntb->ctx_lock);
122 
123 	return device_register(&ntb->dev);
124 }
125 EXPORT_SYMBOL(ntb_register_device);
126 
ntb_unregister_device(struct ntb_dev * ntb)127 void ntb_unregister_device(struct ntb_dev *ntb)
128 {
129 	device_unregister(&ntb->dev);
130 	wait_for_completion(&ntb->released);
131 }
132 EXPORT_SYMBOL(ntb_unregister_device);
133 
ntb_set_ctx(struct ntb_dev * ntb,void * ctx,const struct ntb_ctx_ops * ctx_ops)134 int ntb_set_ctx(struct ntb_dev *ntb, void *ctx,
135 		const struct ntb_ctx_ops *ctx_ops)
136 {
137 	unsigned long irqflags;
138 
139 	if (!ntb_ctx_ops_is_valid(ctx_ops))
140 		return -EINVAL;
141 	if (ntb->ctx_ops)
142 		return -EINVAL;
143 
144 	spin_lock_irqsave(&ntb->ctx_lock, irqflags);
145 	{
146 		ntb->ctx = ctx;
147 		ntb->ctx_ops = ctx_ops;
148 	}
149 	spin_unlock_irqrestore(&ntb->ctx_lock, irqflags);
150 
151 	return 0;
152 }
153 EXPORT_SYMBOL(ntb_set_ctx);
154 
ntb_clear_ctx(struct ntb_dev * ntb)155 void ntb_clear_ctx(struct ntb_dev *ntb)
156 {
157 	unsigned long irqflags;
158 
159 	spin_lock_irqsave(&ntb->ctx_lock, irqflags);
160 	{
161 		ntb->ctx_ops = NULL;
162 		ntb->ctx = NULL;
163 	}
164 	spin_unlock_irqrestore(&ntb->ctx_lock, irqflags);
165 }
166 EXPORT_SYMBOL(ntb_clear_ctx);
167 
ntb_link_event(struct ntb_dev * ntb)168 void ntb_link_event(struct ntb_dev *ntb)
169 {
170 	unsigned long irqflags;
171 
172 	spin_lock_irqsave(&ntb->ctx_lock, irqflags);
173 	{
174 		if (ntb->ctx_ops && ntb->ctx_ops->link_event)
175 			ntb->ctx_ops->link_event(ntb->ctx);
176 	}
177 	spin_unlock_irqrestore(&ntb->ctx_lock, irqflags);
178 }
179 EXPORT_SYMBOL(ntb_link_event);
180 
ntb_db_event(struct ntb_dev * ntb,int vector)181 void ntb_db_event(struct ntb_dev *ntb, int vector)
182 {
183 	unsigned long irqflags;
184 
185 	spin_lock_irqsave(&ntb->ctx_lock, irqflags);
186 	{
187 		if (ntb->ctx_ops && ntb->ctx_ops->db_event)
188 			ntb->ctx_ops->db_event(ntb->ctx, vector);
189 	}
190 	spin_unlock_irqrestore(&ntb->ctx_lock, irqflags);
191 }
192 EXPORT_SYMBOL(ntb_db_event);
193 
ntb_probe(struct device * dev)194 static int ntb_probe(struct device *dev)
195 {
196 	struct ntb_dev *ntb;
197 	struct ntb_client *client;
198 	int rc;
199 
200 	get_device(dev);
201 	ntb = dev_ntb(dev);
202 	client = drv_ntb_client(dev->driver);
203 
204 	rc = client->ops.probe(client, ntb);
205 	if (rc)
206 		put_device(dev);
207 
208 	return rc;
209 }
210 
ntb_remove(struct device * dev)211 static int ntb_remove(struct device *dev)
212 {
213 	struct ntb_dev *ntb;
214 	struct ntb_client *client;
215 
216 	if (dev->driver) {
217 		ntb = dev_ntb(dev);
218 		client = drv_ntb_client(dev->driver);
219 
220 		client->ops.remove(client, ntb);
221 		put_device(dev);
222 	}
223 
224 	return 0;
225 }
226 
ntb_dev_release(struct device * dev)227 static void ntb_dev_release(struct device *dev)
228 {
229 	struct ntb_dev *ntb = dev_ntb(dev);
230 
231 	complete(&ntb->released);
232 }
233 
234 static struct bus_type ntb_bus = {
235 	.name = "ntb",
236 	.probe = ntb_probe,
237 	.remove = ntb_remove,
238 };
239 
ntb_driver_init(void)240 static int __init ntb_driver_init(void)
241 {
242 	return bus_register(&ntb_bus);
243 }
244 module_init(ntb_driver_init);
245 
ntb_driver_exit(void)246 static void __exit ntb_driver_exit(void)
247 {
248 	bus_unregister(&ntb_bus);
249 }
250 module_exit(ntb_driver_exit);
251 
252