drivers/ntb/ntb.c

   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
  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
  94 void ntb_unregister_client(struct ntb_client *client)
  95 {
  96         driver_unregister(&client->drv);
  97 }
  98 EXPORT_SYMBOL(ntb_unregister_client);
  99
 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
 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
 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
 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
 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
 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
 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
 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
 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
 240 static int __init ntb_driver_init(void)
 241 {
 242         return bus_register(&ntb_bus);
 243 }
 244 module_init(ntb_driver_init);
 245
 246 static void __exit ntb_driver_exit(void)
 247 {
 248         bus_unregister(&ntb_bus);
 249 }
 250 module_exit(ntb_driver_exit);
 251